Unit 1 Lesson 2 Quiz

Which of these is an example of the transformation of kinetic energy into gravitational potential energy?

• a person walking up a hill

• a person skiing down a hill

• a car racing around an oval track

• a person parachuting out of an airplane

How is mechanical energy calculated?

• by adding potential energy and kinetic energy

• by dividing potential energy by kinetic energy

• by multiplying potential energy and kinetic energy

• by subtracting potential energy from kinetic energy

The diagram shows the curved path of a thrown ball. At what point does it have the highest amount gravitational potential energy?

• point W

• point X

• point Y

• point Z

Which of these has the most kinetic energy?

• a 25 kg fish tank sitting on a table

• a 50 g fish swimming in a fish tank

• a 7,500 kg car parked on a steep hill

• a 50 kg boulder suspended from a cliff

The diagram shows a swinging pendulum. During every swing, the pendulum’s speed and position change. Three positions during the swing are identified as Position 1, Position 2, and Position 3. At which point would most of the pendulum’s potential energy have been transformed into kinetic energy?

• Position 1

• Position 2

• Position 3

• The potential and kinetic energies are equal in all positions

Which change would increase the kinetic energy of a moving object the most?

• reducing the mass by half

• reducing the speed by half

• doubling the mass of the object

• doubling the speed of the object

Which of these statements is an example of energy transfer?

• an open flame heating a pan of water

• a plant using sunlight to create glucose

• turning on a flashlight to create a beam of light

• a child rubbing her hands together to warm them

A 40 kg girl is pushing a 40 kg boy in a 20 kg toy wagon.
The wagon is moving at a constant speed of 2.0 m/s. Calculate the combined kinetic energy of the boy and the wagon. Remember

 $KE\ =\ \frac{1}{2}mv^2$  

A 40 kg girl is pushing a 40 kg boy in a 20 kg toy wagon.The wagon is moving at a constant speed of 2.0 m/s.

They come to a hill going downward, and the girl joins the boy in the wagon, which continues to move at 2.0 m/s at first. Calculate the combined kinetic energy of the two children and the wagon.

A 40 kg girl, 40 kg boy in a 20 kg toy wagon.

As they travel down the hill, the wagon speeds up to 4.0 m/s. Calculate the kinetic energy of the two children and the wagon after the increase in speed.