PHYS Quiz

An object is falling is falling on the moon, where the acceleration due to gravity is 2 m/s/s. If the object is dropped from rest, what speed will the object have after 5 seconds of freefall?

10 m/s

A 10 kg brick and a 1 kg book are dropped in a vacuum. The force of gravity on the 10 kg brick is _____

10 times as much as the force on the 1 kg book

A jumbo jet has a mass of 100,000 kg. The thrust for each of four engines is 50,000 N. What is the jet's acceleration in meters per second per second when taking off?

2

Exert 100 Joules in 50 seconds and your power output is

2 W

A car has a mass of 1000 kg and accelerates a 2 m/s/s. What is the magnitude of the net force exerted on the car?

2000 N

On the surface of Jupiter, where the acceleration due to gravity is about 3 times that of Earth, a 100 kg rock would have a weight of about _____

3000 N

A bow is drawn so that it has 40 J of potential energy. When fired, the arrow will ideally have a kinetic energy of

40 J

A driver who weighs 500 N steps off a diving board that is 10 meters above the water. The diver hits the water with kinetic energy of

5000 J

The weight of 0.6 kg of salami is about ________

6.0 N

Which requires more work: lifting a 50 kg sack vertically 2 meters or lifting a 25 kg sack vertically 4 times?

Both require the same amount of work

Two objects are the same height above the ground. One of the objects has twice as much mass as the other. The one that is double the mass _____.

Has twice the gravitational potential energy as the smaller mass

An object following a straight-line path at constant speed _______.

Has zero acceleration

If you double the speed of an object, what happens to its kinetic energy?

It's quadrupled

A rock is thrown vertically into the air. At the top of its trajectory, the net force on it is _________.

It's weight

A heavy rock and a light rock in free fall have the same acceleration. The reason the heavy rock doesn't have a greater acceleration is that the ____.

Ratio of force to mass is the same

Which requires the most amount of work on the brakes of a car

Slowing down from 100 km/h to 70 km/hr

A 1 kg ball has the same speed as a 10 kg ball. Compared with the 1 kg ball, the 10 kg ball has

Ten times as much momentum

The attraction of a person's body toward the Earth is called weight. The reaction to this force is _____.

The person's body pulling on the Earth

An object is raised above the ground gaining a certain amount of gravitational potential energy. If the same object is raised twice as high it gains ____

Twice as much potential energy

The force required to maintain an object at a constant velocity in free space is equal to ____.

Zero

When a ball decreases in speed by the same amount each second, it's acceleration ________

is constant and non-zero

If the mass of a grocery cart decreases to half and its speed doubles, the momentum of the cart _____.

remains unchanged