Forces, Energy, Work and Power

How can you increase the potential energy?

• by dropping an object

• by making an object move faster

• by lifting an object higher

• by burning an object

A bicycle rider is traveling up a hill. When the rider reaches the top of the hill, she stops to rest. Then she travels down the hill. The diagram show the rider in the three different positions.

• When the rider is at the top of the hill, her potential energy is the greatest, and her kinetic energy is the least.

• As the rider moves up the hill, her kinetic energy increases, and her potential energy decreases.

• When the rider goes down the hill, her potential energy increases, and her kinetic energy decreases.

• As the rider reaches the bottom of the hill, her kinetic energy and her potential energy decrease.

What is the kinetic energy of a 4 kg TV that was thrown out he window with a speed of 2 m/sec?

• 8 J

• 6 J

• 2 J

• 4 J

What is the energy of a 1.071 kg medicine ball that is falling from a height of 2m? (P.E=mxgxh where g=9.8m/s2)

• 2.142 J

• 0.21 J

• 20.99 J

• 3.07 J

What is the gravitational potential energy of a 0.3061 kg baseball that is falling from the second floor that is 5m high? (P.E= mgh, g=9.8 m/s2)

• 3 J

• 1.5 J

• 67.5 J

• 15 J

At which position does the cart have the greatest potential energy and the least kinetic energy?

• a

• b

• c

• d

As the skateboarder travels down the hill, he's kinetic energy -

• will decrease

• will increase

• will remain the same

• will transfer to potential energy

Moving water and wind are examples of .....

• potential energy

• chemical energy

• elastic energy

• kinetic energy

This increases the _______________________ energy of the spring.

• kinetic

• potential

• chemical

• electrical

Which will have the greatest acceleration?

• boy and car

• boy and lawnmower

• they will have equal acceleration