WPE Review

A 1.0 x 10³ kilogram car is moving at a constant speed of 4.0 meters per second. What is the kinetic energy of the car?

• 1.6 x 10³ J

• 2.0 x 10⁴ J

• 8.0 x 10³ J

• 4.0 x 10³ J

A 60.0 kilogram runner has 1920 joules of kinetic energy. At what speed is she running?

• 5.66 m/s

• 8.00 m/s

• 32.0 m/s

• 64.0 m/s

When a 5 kilogram mass is lifted from the ground to a height of 10 meters, the gravitational potential energy of the mass is increased by approximately

• 0.5 J

• 2 J

• 50 J

• 500 J

A cart weighing 10 Newtons is pushed 10 meters on a level surface by a force of 5 Newtons. What is the increase in its potential energy?

• 1 joule

• 50 joules

• 100 joules

• 0 joules

A 10. newton force is required to hold a stretched spring 0.20 meter from its rest position. What is the potential energy stored in the stretched spring?

• 1.0 J

• 2.0 J

• 5.0 J

• 50 J

A constant force of 2.0 Newtons is used to push a 3.0 kilogram mass 4.0 meters across the floor. How much work is done on the mass?

• 6 J

• 8 J

• 12 J

• 24 J

In the associated diagram, a 20.0 newton force is used to push a 2.00 kilogram cart a distance of 5.00 meters. The work done on the cart is

• 100 J

• 200 J

• 150 J

• 40 J

A crate is pulled 6.0 meters up an incline with a force of 50 Newtons. If the potential energy of the box increases 250 joules, the total work done against friction in moving the box is

• 0 J

• 50 J

• 250 J

• 300 J

A block weighing 15 Newtons is pulled to the top of an incline that is 0.20 meter above the ground, as show in the associated picture. If 4.0 joules of work are needed to pull the block the full length of the incline, how much work is done against friction?

• 1 J

• 0 J

• 3 J

• 7 J

As the time required to do a given quantity of work decreases, the power developed

• decreases

• increases

• remains the same