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MCAT Physics Review
MCAT Physics Review, Practice, and Strategies
Question | Answer |
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1. A man walks three blocks (30m) east and then another five blocks (50m)north to the drugstore (point B). What is the magnitude of his final displacement from his original location (point A)? | 1. C - 60 m |
2. A submarine sends out a sonar sound wave in a direction directly downward. It take 2.3s for the sound to travel from the sub to the ocean bottom & back to the sub. How high up from the ocean floor is the sub? (The speed of sound in water is 1489 m/s) | 2. A - 1700 m |
3. A car is traveling at 40 km/hr & the driver puts on the brakes, bringing the car to rest in a time of 6 s. What is the magnitude of the average acceleration of the car in units of km/hr²? | 3. C - 24,000km/hr² |
4. If an object is released 19.6 m above the ground, how long does it take the object to reach the ground? | 4. B - t= 2 s |
5. At a place where is g is 9.8 m/s², an object is thrown vertically downward w/ a speed of 10 m/s while a different object is thrown vertically upward w/ a speed of 20 m/s. Which object undergoes a greater change in speed in time of 2 s? | 5. C - Both objects undergo the same change in speed |
6. A firefighter jumps horizontally from a burning building w/ initial speed of 1.5 m/s. At what time is the angle between his velocity & acceleration the greatest? | 6. A - The instant he jumps |
7. A circus clown is catapulted straight up in the air (the catapult is 1.5 m off the ground level). If her velocity as she leaves the catapult is 4 m/s, what is the maximum height that she reaches, as measured from the ground? | 7. D - 2.3 m |
8. Which of the following expressions correctly illustrates the SI units of each one of the variables in the formula? | 8. C - g x m/s = N x s |
9. If a toy magnet is able to generate one centitesla, how many teslas would 10⁸ magnets be able to generate? | 9. B - 1 MT |
10. Which of the following quantities is NOT a vector? | 10. D - Distance |
11. A rifle is held by a man whose arms are 1.5 m above the ground. He fires a bullet at 100 m/s at an angle of 30° w/ the horizontal. After 2 s, how far has the object traveled in the horizontal direction? | 11. C - 174 m |
12. A BASE jumper runs off a cliff w/ a speed of 3 m/s. What is his overall velocity after 0.5 seconds? | 12. B - 6 m/s |
13. A rock (m= 2 kg) is shot up vertically at the same time that a ball (m= 0.5 kg) is projected horizontally. If both start from the same height, | 13. C - the ball will reach the ground first |
1. Two men, holding identical bullets, stand side by side in a large field. One uses a gun to shoot his bullet across the field while the other simultaneously drops his bullet from the same height as the gun. Which bullet will hit the ground first, assumi | 1. 2 bullets= same height above ground, same gravitational force in downward direction, & hit the ground at the same time. Bullet shot= a horizontal velocity that has no force=> horizontal motion has no effect on the acceleration of the bullet to |
2. The Richter scale uses a logarithmic function to rate the intensity of earthquakes. How does the intensity of a 3 earthquake compare to a 5 earthquake on the Richter scale? | 2. The logarithmic scale means that when an earthquake increases ten-fold in intensity, or amplitude, its Richter magnitude will increase by 1 point on the Richter scale=> a 3 earthquake has an amplitude only one-hundredth that of a 5 earthquake. |
1. A 1,000 kg rocket ship, traveling at 100 m/s, is acted on by an average force of 20 kN applied in the direction of its motion for 8 s. what is the change in velocity of the rocket? | 1. B - 160 m/s |
2. An elevator is designed to carry a max weight=9800 N including its own weight & to move upward at a speed =5 m/s after an initial period's acceleration. What is the relationship between the max tension in the elevator cable & the max weight of 9800 N w | 2. A - The tension is greater than 9800 N |
3. a 10 kg wagon rests on a frictionless inclined plane. The plane makes an angle of 30 degrees w/ the horizontal. what is the force, F, required to keep the wagon from sliding down the plane? | 3. C - 49 N |
4. A 20 kg wagon is released from rest from the top of a 15 m long plane, which is at 30 degrees w/ the horizontal. Assuming there is friction between the ramp & the wagon, how is this frictional force affected if the angle of the incline is increased? | 4. B - The frictional force decreases. |
5. An astronaut weights 700 N on Earth. What is the best approximation of her new weight on planet w/ a radius that is two times that of Earth, & a mass three times that of Earth? | 5. B - 500 N |
6. A 30 kg girl sits on a seesaw at a distance of 2 m from the fulcrum. Where must her father sit to balance the seesaw if he has a mass of 90 kg? | 6. B - 67 cm from the fulcrum |
7. An object is moving uniformly in a circle whose diameter is 200 m. If the centripetal acceleration of the object is 4 m/s2, then what is the time for one revolution of the circle? | 7. A - 10 pi s |
8. A distant solar system's made up 1 small planet of mass 1.48x10 pwr 24 kg revolving in a circular orbit about a large, stationary star of mass 7.3x10 pwr 30 kg. The distance between their center is 5x10 pwr 11 m. What happens to the speed of the planet | 8. B - The speed of the planet decreases |
9. An elevator is accelerating down at 4 m/s2. How much does a 10 kg fish weight if measured inside the elevator? | 9. C - 60 N |
10. A 1 kg ball w/ a radius of 20 cm rolls down a 5 m high inclined plane. Its speed at the bottom is 8 m/s. How many revolutions per second is the ball making when at the bottom of the plane? | 10. A - 6 revolutions/s |
11. A 1000 kg satellite traveling at speed v maintains an orbit of radius R around the Earth. What should be in speed if it is to develop a new obit of radius 4R? | 11. B - ½ v |
12. A 100 kg elevator initially at rent accelerates up at rate vector a. What is the average force acting on the elevator if it convers a distance x over a period of 10 s? | 12. A - 2x + 1000 |
1. A weight lifter lifts a 275 kg barbell from the ground to a height of 2.4 m. How much work has he done, & how much work is required to hold the weight at that height? | 1. C - 6,468 J & 0 J, respectively |
2. A tractor pulls a log w/ 500 kg along the ground for 100 m. The rope (between the tractor & the log) makes 30 degrees w/ the ground & is acted on by a tensile force 5000 N. How much work does the tractor do? (sin30=0.5, cos30= 0.866, tan30=0.57) | 2. C - 433 kJ |
3. A 2000 kg experimental car can accelerate from 0 to 30 m/s in 6.3 s. What is the average power of the engine needed to achieve this acceleration? | 3. B - 143 kW |
4. A 40 kg block is resting at a height of 5 m off the ground. If the block is released & falls to the ground, what is its total energy at a height of 2 m? | 4. C - 2 kJ |
5. If human's lying on a flat surface&the weights of the head,thorax,&hips&legs are 8,10,&20 lbs,respectively, what is the center of mass of this person? (Assume that the centers of mass of the head,thorax,&hips&legs are 5,25,&50 inches from the top of th | 5. C - 30 niches away from the top of the head |
6. In the pulley system shown, if the mass of the object is 10 kg & the object is accelerating upward at 2 m/s2, what is the tension force in each rope? | 6. B - 60 N |
7. Two billiard balls, one moving @0.5 m/s, the other at rest, undergo an elastic collision. If the billiard balls' masses are equal & the speed of the stationary one after the collision is 0.5 m/s, what is the speed of the other ball after the collision? | 7. A - 0 m/s |
8. A 2500 kg car traveling @ 20 m/s crashes into a 6000 kg truck that is originally at rest. What is the speed of the truck after the collision, if the car comes to rest @ the point of impact? (Neglect the effects of friction) | 8. B - 8.33 m/s |
9. Which of the following are elastic collision? | 9. B - II only |
10. A 1 kg cart travels down an inclined plane @5 m/s &strikes 2 balls which start moving in opposite directions perpendicular to the direction of the cart. Ball A has 2 kg & moves away @2 m/s, while ball B has 1 kg & moves away @4 m/s. Which one is true? | 10. C - The cart will continue moving as before, while balls A & B will convert the gravitational potential energy of the cart into their own kinetic energies. |
11. Tom, who has 80 kg, & Mary, who has 50 kg, jump off a 20 m tall building & land on a fire net. The net compresses, & they bounce back up at the same time. which of the following statements is NOT true? | 11. A - Mary will bounce higher than Tom. |
12. Two identical molecules, A&B, move w/ the same horizontal velocities but opposite vertical velocities. which of the following statements MUST be true after the two molecules collide? | 12. A - The sum of the kinetic energies of the molecules after the collision is less than the sum of the kinetic energies of the molecules before the collision. |
1. If an object w/ an initial temperature of 300 K increases its temperature by 1 K every minute, by how many degrees Celsius will its temperature have increased in 10 minutes? | 1. A - 10°C |
2. Which of the following choices correctly identifies the following three heat transfer processes? 1. Heat transferred from the Sun to the Earth 2. A metal spoon heating up when placed in a pot of hot soup 3. A rising plume of smoke from a fire | 2. A - 1. Radiation; 2. Conduction; 3. Convection |
3. A 20 m steel rod at 10°C is dangling from the edge of a building & is 2.5 cm from the ground. If the rod is heated to 90°C, will it touch the ground? (α = 1.1 x 10⁻⁵K⁻¹) | 3. C - No, because it only expands by 1.6 cm |
4. What is the final temperature of 5 kg silver pendant that is left in front of an electric heater & absorbs heat energy @ a rate 100W for 10 min? Assume the pendant is initially @ 20°C & that the specific heat of silver is c= 236 J/kg°C | 4. C - 71°C |
5. How much heat is required to completely melt 500g gold earrings, given that their initial temperature is 25°C? The melting point of gold is 1064.18°C, the heat of fusion is 6.45 x 10⁴J/kg, & the specific heat is 129 J/kg°C | 5. D - 65 kJ |
6. Given the cycle shown, what is the total work done by the gas in the cycle? | 6. C - 7.5 J |
7. In an adiabatic compression process, the internal energy of the gas | 7. B - increases, because the work done on the gas is positive |
8. The entropy of a system can | 8. B - decrease when the entropy of the surroundings increases by at least as much |
9. The internal energy of an object increases in an adiabatic process. Which of the following must be true regarding this process? | 9. C - Work is done on the system |
10. A certain substance has a specific heat of 1 J/mol.K & a melting point of 350 K. If one mole of the substance is currently at a temperature of 349 K, how much energy must be added in order to melt it? | 10. A - More than 1 J |
12. The figure shown depicts a thick metal container w/ two compartments. Compartment A is full of a hot gas, while compartment B is full of a cold gas. What is the primary mode of heat transfer in this system? A B | 12. C - Conduction |
13. Substances A & B have the same freezing & boiling points. If solid samples of both substances are heated in the exact same way, substance A boils before substance B. Which of the following would NOT explain this phenomenon? | 13. D - Substance B has a higher internal energy |
14. In experiment A, a student mixes ink w/ water & notices that the two liquids mix evenly. In experiment B, the student mixes oil w/ water; in this case, the liquids separate into two different layers. The entropy change is | 14. B - positive in experiment A and zero in experiment B |
15. Which of the following processes is LEAST likely to be accompanied by a change in temperature? | 15. C - A boiling liquid is heated on a hot plate |
1. Object A & B are submerged at a depth of 1 m in a liquid w/ a specific gravity of 0.879. Given that the density of object B is ⅓ that of object A and that the gauge pressure of object A is 3 atm, what is the gauge pressure of object B? (g=9.8 m/s²) | 1. C - 3 atm |
2. An anchor made of iron weighs 833 N on the deck of a ship. If the anchor is now suspended in seawater by a massless chain, what is the tension in the chain? (The density of iron is 7800 kg/m³, & the density of seawater is 1024 kg/m³) | 2. B - 724 N |
3. Two=volume balls,≠ density are held beneath the surface of container of water.Balls A's & B's densities 0.5&0.7 g/cm³ respectively.When releasing the balls,they accel. upward to the surface. What is the relationship between accel. of balls A&B?ᵨ=1g/cm³ | 3. A - Ball A has the greater acceleration |
4. Water flows from a pipe of diameter 0.15 m into one of diameter 0.2 m. If the speed in the 0.15 m pipe is 4.88 m/s, what is speed in the 0.2 m pipe? | 4. B - 2.7 m/s |
5. Used A hydraulic lever to lift a hospital bed by a work W˳. When a bed&patient's lifted, the work is doubled.How can the cross-sectional area of the platform on which the bed's lifted be changed so that the pressure on hydraulic lever remains constant? | 5. A - The cross-sectional area must be doubled |
6. The figure shown represents a section through a horizontal pipe of varying diameters into which 4 open vertical pipes connect. If water flows through the pipe in the direction indicated, in which of the vertical pipe will the water level be lowest? | 6. B - Pipe 2 |
7. the speed of blood in the aorta is much higher than the speed of blood through the capillary bed. How can this fact be explained using the continuity equation? | 7. C - The cross-sectional area of all of the capillaries added together is much greater than the cross-sectional area of the aorta |
8. A student measures the gelatin's shear modulus. When applying an amount of stress to a piece of rubber, measure strain=3 (Young's modulus:rubber=0.1Pa).When applying the same stress to a piece of gelatin,strain=6.What's the gelatin's shear modulus? | 8. A - 0.05 P |
10. An oddly shaped water-filled sculpture is allowed water levels to change depending on a force applied @ the tank's top.If F₁=4N is applied to a square,flexible cover where A₁=16&the area A₂=64,what force is applied to A₂ so water levels fr changing? | 10. B - No force needs to be applied |
11. Balls A & B of equal mass are floating in a swimming pool, as in the figure shown. which will produce a greater buoyant force? | 11. C - The forces will be equal |
12. Bernoulli's principle is the reason for the upward force that permits a lift force to cause airplane flight. What statement best summarizes the principle's relationship to fight? | 12. B - The speed of airflow is greater over the curved top of the wing, resulting in less pressure on the top of the wing & the production of a net upward force on the wing, in turn resulting in flight |
13. A low-pressure weather system can decrease the atmospheric pressure from 1 to 0.99 atm. By what percent will this decrease the force bearing on a rectangular window, 6 by 3 m from the outside. The glass is 3cm thick. | 13. A - 1% |
2. If the distance between the centers of the spheres is halved, the magnitude of the force on S due to R will | 2. D - 4F |
3. If an electron were placed midway between R & S, the restaurant electric force on the electron would be | 3. B - toward S |
4. If the electric field at a distance r away from charge Q is 36 N/C, what is the ratio of the electric fields at r,2r,&3r? | 4. A - 36:9:4 |
5. A positive charge +Q's fixed @R a distance d away from another positive charge +2Q fixed @S. Point A's located midway between the charges, & B's a distance d/2 from +2Q. In which direction will a positive charge move if placed @A? ____d____ +Q← A→+2Q | 5. A - Toward the +Q charge |
6. Two parallel conducting plates, +Q & -Q, are separated by a distance d. The voltage between the plates is 12 V. If a +2µC charge is released from the rest @ the positive plate, how much kinetic energy does it have when it reaches the negative plate? | 6. B - 2.4 x 10⁻⁶J |
8. If the electric field at 3 m away from a charge is 8 N/C, what is the electric potential at a point 6 m away from the charge? | 8. C - 12 V |
9. Given an electric dipole, the electric potential is zero | 9. B - anywhere on any perpendicular bisector of the dipole axis and at infinity |
10. The electric potential applied to a certain electron is increased by a factor of | 10. D - 2 |
12. A certain 9-volt battery is used as a power source to move a 2 C charge. How much work is done by the battery? | 12. C - 18 J |
13. A proton & an alpha particle (a helium nucleus) repel each other w/ a force of F while they are 20 nm apart. If each particle combines w/ three electrons, what is the new force between them? | 13. C - F |
1. A negative charge placed in an external magnetic field circulates counterclockwise in the plane of the paper as shown. In which direction is the magnetic field pointing? | 1. B - Out of the page |
3. Which of the following is NOT a necessary condition for having a magnetic force on a particle? | 3. D - The particle must have a certain length |
4. If the magnetic field (M.F.) a distance r away fr. a wire is 10T, what'll be the total M.F. at r if another wire's placed @ 2r from the original wire & has a current twice as flowing in the opposite direction? The M.F. generated by wire B=µₒI/2∏r | 4. D - 30 T |
7. A circular loop of wire r=20cm,a current i=5A. A + charged particle w/ velocity perpendicular to the plane of the loop passes directly through the center of the loop. What's the force on the charged particle the instant it passes through the center? | 7. A - 0 N |
8. A 6.5 MeV proton cyclotron's to be built, but it must fit into 10m x 10m rom in the basement of the hospital. The max M.F.= 1T, can the hospital go ahead w/ its plans? The mass of a proton=1.67x10¯²⁷kg, & the charge of a proton= 1.6x10ˉ¹⁹C | 8. A - Yes, because the magnetic field (M.F.) needed is smaller that in the maximum M.F. attainable |
9. Two positive charges are traveling in opposite directions parallel to the uniform magnetic field. It can be inferred that the magnetic force on both charges | 9. C - is zero |
10. A negatively charged particle of C and 0.005 g is spinning in a uniform magnetic field along the circle w/ a radius of 8 cm. Knowing that the strength of the magnetic field is 5T, calculate the speed of the particle | 10. C - 1.6 x 10⁵ m/s |
11. A power cable, stretched 8m above the ground, is carrying 50A of current. Determine the magnetic field produced by the current at the ground level under the wire if µₒ, the permeability of free space, is 1.26 x10¯⁶T | 11. A - 1.26 x 10¯⁶ T |
12. A researcher is interested in creating a particle accelerator that can spin particles in the uniform magnetic field at the highest possible speed. This can be achieved by all of the following EXCEPT | 12. B - increasing mass of the particles |
13. A proton and an electron are traveling in the uniform magnetic field w/ identical velocities. If the movement of both particles is perpendicular to the magnetic field lines, which of the following is/are NOT true? | 13. D - I, II, & III |
14. A velocity filter detects particles of particular speed at the point when electric force F= Eq & M.F. F= qvB produced by the filter are equal. It can be reasonably assumed that, in order to select a particle w/ a higher speed, one should increase | 14. A - the electric field |
1. If a defibrillator passes 15 A of current through a patient's body for 0.1 seconds, how much charge goes through the patient's skin? | 1. B - 1.5 C |
2. A charge of 2µC flows from the positive terminal of a 6V battery, through a 100 ohms resistor, & back through the battery to the positive terminal. What is the total voltage drop experienced by the charge? | 2. A - 0V |
3. If the resistance of two conductors of equal cross-sectional area & equal lengths are compared, they are found to be in the ratio 1:2. The resistivity of the materials from which they are constructed must therefore be in what ratio? | 3. B - 1:2 |
4. If a voltaic cell provides a current of 0.5A, the resistor in the circuit has a resistance of 3 ohms, & the internal resistance of the battery is 0.1 ohm, what is the voltage across the terminals of the battery when there is no current flowing? | 4. D - 1.55 V |
9. If the area of a capacitor's plates is doubled while the distance between them is halved, how will the final capacitance (Cᶠ) compare to the original capacitance (Ci)? | 9. D - Cᶠ= 4Ci |
10. The energy stored in a fully charged capacitor (C) by E=1/2 CV². In a cardiac defibrillator, a C charged to 7500V has a stored energy of 400Ws. If the charge Q & voltage V on a C are related by Q=CV, what's Q on the C in the cardiac defibrilator? | 10. C - 1.1 x 10¯¹C |
13. Which of the following will most likely increase the electric field between the plates of a parallel plate capacitor? | 13. D - Adding an extra battery to the system |
1. If the length of a pendulum is increased from 2m to 8m, how will the period of oscillation be affected? | 1. A - It will double |
2. A child is practicing the second harmonic on his flute. If his brother covers one end of the flute for a brief second, how will the sound change? | 2. B - the pitch of the sound will be lower |
3. A mass is attached to a horizontal spring & moved horizontally on a frictionless surface. The mass is displaced from equilibrium & released. At what point does the mass experience the min force from the spring & its maximum acceleration respectively? | 3. C - At the equilibrium point; at maximum compression or expansion |
4. How far away from equilibrium will the kinetic energy be equal to the potential energy for a spring that has a spring constant k= 0.1 N/m, a speed of 3 m/s, &a 0.4 kg mass attached? | 4. B - 6 m |
5. At what frequency will a spring w/ an attached mass resonate? | 5. A - 1/(2∏).(k/m)½ |
6. If the speed of a wave is 3 m/s & its wavelength is 10cm, what is the period? | 6. B - 0.03 s |
7. What is the angular frequency of a sound in the third harmonic that comes out of a pipe w/ one end closed? the length of the pipe L= 0.6m, & the speed of the sound is 340 m/s | 7. D - 800 ∏ |
8. a certain sound level is increased by an additional 10 dB. By how much does its intensity increase? | 8. C - 100 |
10. If two waves are 180⁰ out of phase, what is the amplitude of the resultant wave if the amplitudes of the original waves are 5cm & 3cm? | 10. A - 2 cm |
11. A student's standing on the side of a road, facing east, & measuring sound frequencies. For which of the following situations would the student determine that the difference between the perceived frequency & the actual emitted frequency is zero? | 11. C - A person playing piano right behind the student |
12. In which of the following media does sound travel the fastest? | 12. D - Glass |
13. A mass on a pendulum oscillates via simple harmonic motion. A student wants to double the period of the system. She can do this by taking which of the following actions? | 13. B - III only |
14. As an officer approaches a student who is studying w/ his radio playing loudly beside him, he experiences the Doppler effect. Which of the following statements remains true as the officer moves closer to the student? | 14. A - I only |
15. If the frequency of a pendulum is four times greater on an unknown planet than it is on earth, then the gravitational constant on that planet is | 15. A - 16 times greater |
1. If a light ray has a frequency of 5.0 x 10¹⁴Hz, in which region of the electromagnetic spectrum can it be located? | 1.C - Visible |
2. A standing child has a plane mirror 5m away from his left arm & another plane mirror 7m away from his right arm. How far apart are the two images produced by the mirrors if the child has an arm span of 0.5m? | 2.D - 24.5 m |
3. An object is placed at the center of curvature of a concave mirror. Which of the following is true about the image? | 3.A - It is real & inverted |
4. When monochromatic light is refracted as it passes from air to glass, which of the following does not remain the same? Assume the wave is fully transmitted. | 4.A - Wavelength |
6. A source of light f=3.0x10⁸Hz passes through 3 polarizers. The first two polarizers are in the same direction, while the third is rotated 90° w/ respect to the second polarizer. What is the frequency of the light that comes out to the third polarizer? | 6.A - Light will not pass through the third polarizer |
8. Which of the following describes the image formed by an object placed in front of a convex lens at a distance smaller than the focal length? | 8.B - Virtual & upright |
9. A submarine's inspecting the surface of water w/ a laser that points from the submarine to the surface of the water & thr. the air. At what angle'll the laser not penetrate the surface of water but rather reflect back into water; n=2(water) & n=1(air) | 9.D - 35° |
10. Student's analyzing the behavior of the light ray that's passed thr. a small opening & a lens & allowed to project on a screen a distance away. What happens to the central maximum (the brightest spot on the screen) when the slit becomes narrower? | 10.C - The central maximum becomes wider |
11. Which of the following are able to produce a virtual image? I. Convex lens II. Concave lens III. Plane mirror | 11.D - I, II, & III |
12. Monochromatic red light's allowed to pass between 2 different media. If the angle of incidence in medium 1= 30° & the angle of incidence in medium 2= 45°, what's the relationship between the speed of the light in medium 2 compared to that in medium 1? | 12.A - v₂=v₁√2 |
13. The near/nearest point at which an object can be seen , of one of your eyes= 100cm. You see your friend's face when she stands 50cm in front of you. Using a contact lens to adjust your eyesight, what must be the focal length & power of contact lens? | 13.D - f= 100cm; p= 1 diopter |
14. Beam of monochromatic light originates in air & shine upon the flat surface of a piece of glass @ 60° w/ the horizontal. The reflected & refracted beams are perpendicular to each other. what is the index of refraction of the glass? | 14.D - This scenario is not possible |
1. The Stefan-Boltzmann law says that E's proportional to T⁴, where E's the power/unit area radiated by a body of absolute temperature T. A given body's heated to 380 K & 760 K. what's the ratio of the power per unit area radiated @ higher T to @ lower T? | 1.B - 16 |
3. If the work function of a metal= 2130 J & a ray of light w/ a frequency of 10³⁷Hz is incident on the metal, what will be the speed of the electrons ejected? h=6.63x10⁻³⁴J.s & m=9.1x10⁻³¹kg | 3.C - 10¹⁷ m/s |
4. If the work function of a metal is 4.14 eV & light of frequency 2.42 x10¹⁴Hz is incident on this metal, will there be an ejection of electron? What is the threshold frequency of the metal? h= 4.14x10⁻¹⁵eV.s | 4.A - electrons will not be ejected; fᵼ=10¹⁵Hz |
5. A light of what wavelength must be incident on metal for the ejected electrons to have a kinetic energy of 50 J? The work function of the metal is 16J, & h=6.63x10⁻³⁴J.s | 5.A - 3x10⁻²⁷m |
6. In the hydrogen atom, how many electron states fall in the energy range -10.2 eV to -1.4 eV? | 6.B - 2 |
7. which of the following statements is NOT consistent w/ Bohr's set of postulates regarding the hydrogen atom model w/ regard to the emission & absorption of light? | 7.D - To jump from a higher energy to a lower energy, an electron absorbs a photon of a frequency such that the photon's energy is exactly the energy difference between the two orbits |
8. What is the difference in ionization energy for a hydrogen atom w/ its electron in the ground state & a hydrogen atom w/ its electron in the n=4 state? | 8.C - 12.75 eV |
9. When a hydrogen atom electron falls to the ground state fro the n= 2 state, 10.2 eV of energy is emitted. What is the wavelength of this radiation? 1eV= 1.6x10⁻¹⁹J; h=6.63x10⁻³⁴J.s | 9.A - 1.22x10⁻⁷m |
10. Radiation is emitted from a small window in a large furnace. When the temperature of the furnace is doubled, the peak emitted energy | 10.D - increases by a factor of 16 |
12. Ultraviolet light is more likely to cause a photoelectric effect than visible light. This is because photons of ultraviolet light | 12.D - have a higher energy |
13. All of the following are characteristics of the photoelectric effect EXCEPT | 13.A - The intensity of the light beam does not affect the photocurrent |
1. Which of the following correctly identifies the following process? | 1. C - e⁻ capture |
3. Calculate the binding energy of the argon-40 isotope in MeV using the following information: 1 proton= 1.0073 amu, 1 neutron=1.0087 amu, ⁴⁰Ar=39.9132 amu, C²=932 Mev/amu | 3. A - 0.4096 MeV |
4. An α & β⁺ particles (positron) possess the same kinetic energy. What is the ratio of the velocity of the β⁺ particle to that the α particle? Assume the neutron mass = proton mass & neglect binding energy | 4. B - sqrt[m(proton)/m(electron) |
5. A student is trying to determine the type of nuclear decay for a reaction. Which of the following would be an indication that the reaction he is observing is a gamma decay? | 5. D - Z(daughter)= Z(parent); A(daughter)= A(parent); |
6. Element X is radioactive & decays via α decay w/ a half-life of four days. If 12.5% of an original sample of element X remains after N days, what is the value of N? | 6. C - 12 |
7. A patient undergoing treatment for thyroid cancer receives a dose of radioactive iodine (¹³¹I), which has a half-life of 8.05 days. If the original dose contained 12 mg of ¹³¹I, what mass of ¹³¹I remains after 16.1 days? | 7. A - 3 mg |
8. In an exponential decay, if the natural logarithm of the ratio of intact nuclei(n) at time t=0(nₒ) is plotted against time, what does the slope of the graph correspond to? | 8. B - -λ |
9. The mass of a proton is about 1.007 amu, & the mass of a neutron is about 1.009amu. The mass of a helium nucleus is | 9. A - less than 4.032 amu |
10. A certain carbon nucleus dissociates completely into α particles. How many particles are formed? | 10. C - 3 |
12. the half-life of ¹⁴C is approximately 5730 years, while the half-life of ¹²C in a certain sample is 25% less than the normal ratio in nature, how old is the sample? | 12. A - Less than 5,730 years |
13. a nuclide undergoes 2 α decays, positron decays, & 2 β decays. What is the difference between the atomic number of the parent nuclide & the atomic number of the daughter nuclide? | 13. D - 6 |
14. A helium nucleus fuses w/ a hydrogen nucleus & then captures an electron. What is the identity of the daughter nuclide? | 14. A - ⁵He |
1. Inner electrons are more difficult to eject than outer electrons are because the Bohr energy of outer electrons is | 1. B - closer to zero |
2. Whenever a hole is created by ejected lower-energy electrons, higher-energy electrons drop down to fill this hole because the | 2.D - electron is more stable at lower energy |
5. If scientists discovered a new technique to eliminate Auger electrons, how would this most likely impact the measurement of the energy of x-rays? | 5.A - Decreased error in measurements |
6. Sample A & B both contain the same number of energy levels. On average, the Auger electrons produced by sample A carry more energy than those produced by sample B. Which of the following is most likely true about sample A? | 6.D - It carries a negative charge |
7. Which of the following elements cannot be detected accurately by AES? | 7. A - Helium |
10. An increase voltage across a thermocouple indicates an | 10.C - increased temperature difference across the circuit |
11. If the voltage applied to an RTD is increased, it resistance will | 11.C - remain constant |
12. what type of energy imbalance is responsible for the signal produced within a thermocouple? | 12.A - Potential energy imbalance |
13. Which type of temperature sensor is likely to require an external power source? | 13. C - An RTD, because the resistance can only be measured if external power is available |
15. The thermoelectric effect CANNOT be used to | 16.A - store electricity |
17. The resistivity of a good RTD will most likely be | 17.B - highly variable w/ respect to temperature |
18. What phenomenon can occur w/ light but not w/ sound? | 18.A - Polarization |
19. What is the critical angle for a light wave traveling from a substance w/ an index of refraction of 2 into a vacuum? | 19.A - 30° |
21. when an 8 eV photon strikes a photo- emissive surface, the surface can eject electrons that have at the most a maximum kinetic energy of 6 eV. What is the maximum frequency of the photons being emitted? | 21.B - 1.5 x 10⁻¹⁵ Hz |