Energy in Systems

Amelia is bowling with her family. Her bowling ball followed the path that is shown in the image below. The bowling ball slows down as it travels down the lane. At which point does the bowling ball have the most kinetic energy?

• W

• X

• Y

• Z

Tags

NGSS.MS-PS3-1

NGSS.MS-PS3-5

Two motorboats are traveling down a river. Motorboat 1 has a mass of 6,000 kg, and motorboat 2 has a mass of 1,500 kg. The graph below shows the kinetic energies of the boats as they gain speed. If both boats gain speed at the same rate, why does motorboat 1 have more kinetic energy?

• A. It has more mass.

• B. Its length is greater.

• C. It sits up higher in the water.

• D. It encounters more air resistance.

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NGSS.MS-PS2-2

NGSS.MS-PS3-1

A group of students is having an annual downhill cart race. The unpowered carts, like the one shown below, are lined up at the top of a hill. What gives the cars their potential energy?

• A. their wheels

• B. gravity

• C. their speed

• D. friction

Tags

NGSS.MS-PS2-4

Which of the following variables will affect an object's gravitational potential energy?

• time and kinetic energy

• speed and height

• time and mass

• mass and height

Based on the information in the table, which child has the greatest potential energy at the top of the slide?

• A

• B

• C

• D

Tags

NGSS.MS-PS3-2

Rocks A and B are located at the same height on top of a hill. The mass of rock A is twice the mass of rock B. How does the potential energy of rock B compare to that of rock A?

• Rock B has the same potential energy as rock A.

• Rock B has twice the potential energy of rock A.

• Rock B has one-quarter the potential energy of rock A.

• Rock B has one-half the potential energy of rock A.

Tags

NGSS.MS-PS3-2

The amount of mechanical energy lost by the golf ball is (a)   the amount of heat energy gained by the ball, grass, and air molecules due to friction.

• unrelated to

• equal to

• less than

• greater than

Tags

NGSS.MS-PS3-1

NGSS.MS-PS3-4

When raising the box using the pulley, 4 joules of mechanical energy are converted into heat energy due to friction. What happens to the mechanical energy?

• When raising the box using the pulley, 4 joules of mechanical energy are converted into heat energy due to friction.

• When raising the box using the pulley, 4 joules of mechanical energy are destroyed.

• When raising the box using the pulley, 4 joules of mechanical energy are broken down into protons, neutrons, and electrons.

• When raising the box using the pulley, 4 joules of mechanical energy are transformed into water.

Tags

NGSS.MS-PS1-4

NGSS.MS-PS3-3

A bowling ball travels down a lane and strikes several pins. What happens to the kinetic energy of the bowling ball when it hits the pins?

• A. Most of it is transferred to the pins, but some of it is changed into potential and elastic energy.

• B. All of it is transferred to the pins as thermal energy due to friction.

• C. Most of it is transferred to the pins, but some of it is changed into heat and sound energy.

• D. None of it is transferred to the pins because the bowling ball comes to a stop.

Tags

NGSS.MS-PS2-1

NGSS.MS-PS3-1

NGSS.MS-PS3-5

A car is traveling down a level street at 30 mph. As it approaches a red light, the driver presses the brake pedal. This causes brake pads to squeeze against the wheels and stop the car. According to the law of conservation of energy, what happens to the energy of the car as it travels from position A to position C?

• Position A has the most energy because the kinetic energy is greatest when the car is moving fast.

• Position B has the most energy because the car has kinetic and thermal energy while slowing down.

• Position C has the most energy because the brakes transformed all of the kinetic energy to thermal energy.

• The total amount of energy remains the same, but it is transformed from kinetic energy to thermal energy as the brakes are applied.

Tags

NGSS.MS-PS3-1

NGSS.MS-PS3-5