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PS_Test#2
Question | Answer |
---|---|
A straight-line distance covered during a certain amount of time describes an object's... | speed |
How fast an object is moving in a particular direction is described by... | velocity |
Acceleration occurs when an object undergoes... | (any of the above) speed increase, speed decrease, change in direction |
A car moving at 60km/h comes to a stop in 10s when the driver slams on the brakes. In this situation, what does 60 km/h represent? | Initial speed |
A car moving at 60km/h comes to a stop in 10s when the driver slams on the brakes. In this situation, what is the final speed? | 0km/h |
According to Galileo, an object moving without opposing friction or other opposing forces will... | continue moving at a constant speed |
In free fall, an object is seen to have a(n)... | constant acceleration |
A tennis ball is hit, causing it to move upward from the racket at some angle to the horizon before it curves back to the surface in the path of a parabola. While it moves along this path... | the horizontal speed remains the same |
A quantity of 5m/s^2 is a measure of... | acceleration |
An automobile has how many different devices that can cause it to undergo acceleration? | three or more |
Ignoring air resistance, an object falling toward the surface of Earth has a velocity that is... | increasing |
Ignoring air resistance, an object falling near the surface of Earth has an acceleration that is... | constant |
Two objects are released from the same height at the same time, and one has twice the weight of the other. Ignoring air resistance... | they both hit at the same time |
A ball rolling across the floor slows to a stop because... | there is a net force acting on it |
The basic difference between instantaneous and average speed is that... | average speed is for a total distance over a total time of trip |
Does any change in the motion of an object result in an acceleration? | Yes |
A measure of how fast your speed is changing as you travel to campus is a measure of... | acceleration |
Considering the forces on the system of you and a bicycle as you pedal the bike at a constant velocity in a horizontal straight line... | all forces are in balance, with the net fore equal to zero |
Newton's first law of motion describes... | the tendency of a moving or stationary object to resists any change in its state of motion |
You are standing freely on a motionless shuttle bus. When the shuttle bus quickly begins to move forward, you... | stay in one place over the surface of Earth as the shuttle bus moves from under you |
Mass is measured in kilograms (kg), which is a measure of... | inertia |
Which metric unit is used to express a measure of weight? | N (Newtons) |
Newton's third law of motion states that forces occur in matched pairs that act in opposite directions between two different bodies. This happens... | every time two bodies interact |
If you double the unbalanced force on an object of a given mass, the acceleration will be... | doubled |
If you double the mass of a cart while it is undergoing a constant unbalanced force, the acceleration will be... | one-half as much |
Doubling the distance between the center of an orbiting satellite and the center of Earth will result in what change in the gravitational attraction of Earth for the satellite? | One-fourth as much |
If a ball swinging in a circle on a string is moved twice as fast, the force on the string will be... | four times as great |
A ball is swinging in a circle on a string when the string length is doubled. At the same velocity, the force on the string will be... | one-half as much |
Suppose the mass of a moving scooter is doubled and its velocity is also doubled. The resulting momentum is... | quadrupled |
Two identical moons are moving in identical circular paths, but one moon is moving twice as fast as the other. Compared to the slower moon, the centripetal force required to keep the faster moon on the path is... | four times as much |
Which undergoes a greater change of momentum, a golf ball or the head of a golf club, when the ball is hit from a golf tee? | Both undergo the same change but in opposite directions |
Newton's law of gravitation tells us that... | every object in the universe is attracted to every other object in the universe |
An astronaut living on a space station that is orbiting Earth will... | be in free fall, experiencing apparent weightlessness |
A measure of the force of gravity acting on an object is called... | weight |
1.) You are@rest with a grocery cart@the supermarket when you see a checkout line open&apply a force to the cart for a short time&acquire a speed. Neglecting friction, how long would you have to push with 1/2 the force to acquire the same final speed? | Twice as long |
2.) "...". Neglecting friction doubling the mass would have what effect on the resulting final speed if you used the same force for the same length of time? The new final speed would be... | one-half |
You are moving a grocery cart at a constant speed in a straight line down the aisle of a store. For this situation, the forces on the cart are... | balanced, with a net force of zero |
You are outside a store,moving a loaded grocery cart down the street on a very steep hill.You are able to pull back on the handle&keep the cart moving down the street in a straight line & at a constant speed. The forces on the cart are... | balanced, with a net force of zero |
Neglecting air resistance, a ball in free fall near Earth's surface will have... | increasing speed and constant acceleration |
From a bridge, a ball is thrown straight up at the same time a ball is thrown straight down with the same initial speed. Neglecting air resistance, which ball will have a greater speed when it hits the ground? | Both balls would have the same speed |
After being released, a ball thrown straight up from a bridge will have an acceleration of... | 9.8 m/s^2 |
A gun is aimed horizontally at the center of an apple hanging from a tree. The instant the gun is fired, the apple falls and the bullet... | hits the apple |
According to the third law of motion, which of the following must be true about a car pulling a trailer? | The action-reaction forces between the car and trailer are equal, but the fore between the ground and car pushes them forward. |
A small sports car and a large SUV collide head on and stick together without sliding. Which vehicle had the larger momentum change? | It would be equal for both |
Again consider the small sports car and large SUV that collided head on and stuck together without sliding. Which vehicle must have experienced the larger deceleration during the collision? | The small sports car |
An orbiting satellite is moved from 10,000 to 30,000 km from Earth. This will result in what change in the gravitational attracting between Earth and the satellite? | One-ninth as much |
Newton's law of gravitation considers the product of two masses because... | both masses contribute equally to the force of attraction |