A ball rolls across a carpet, slows, and stops. Afterward the carpet fibers and the nearby air are very slightly warmer. Which claim does this evidence best support?

Two identical carts roll on the same track. Cart A moves at 2 meters per second and Cart B at 4 meters per second. Which claim about their kinetic energy is best supported?

A 1 kilogram cart and a 3 kilogram cart are pushed so that both move at 2 meters per second. Which claim about their kinetic energy is best supported?

A carpenter swings a hammer onto a nail. The hammer stops, the nail moves into the wood, and both the nail and the wood are warmer afterward. What does this evidence support?

A motor spins a paddle inside a sealed container of water for five minutes. A thermometer in the water reads 21 degrees Celsius at the start and 23 degrees Celsius at the end. Which evidence supports energy transfer to the water?

A class claims that a wooden block sliding down a ramp transfers energy to the ramp as it slides. Which extra evidence would best settle this claim?

A cyclist brakes hard and rolls to a stop. The brake pads and wheel rims are noticeably warm to the touch. Which claim best explains both observations together?

A beaker of water is heated on a hot plate and its temperature climbs from 20 degrees Celsius to 60 degrees Celsius. What happened to the water particles?

A hot metal block is placed in a cup of cool water. After several minutes the block and the water read the same temperature. Which claim does this evidence support?

A student drops the same ball into sand twice, once from 1 meter and once from 2 meters. The ball is moving faster when it lands from 2 meters and leaves a deeper hole. Which claim is best supported?

Hot cocoa at 70 degrees Celsius is poured into a foam cup and an identical amount into a metal cup in the same room. Which cup keeps the cocoa hot longer, and why?

A moving object's kinetic energy depends on which factors?

A group claims that a rolling cart transferred energy to a lump of clay when the cart crashed into it. Which finding would most weaken that claim?

A metal spoon and a wooden spoon are both left resting in a pot of hot soup for the same amount of time. The metal spoon feels much hotter to the touch than the wooden spoon. Which claim best explains this observation?

On an air track, a moving cart bumps a still cart. The first cart slows sharply and the second cart starts moving. Which claim does this evidence support?

A cold can of soda is left on a table in a warm room, and after an hour the soda is warmer. Which claim does this evidence support?

Insulation slows the transfer of thermal energy but does not stop it completely.

A student's model says a marble rolling on a smooth floor keeps all its kinetic energy forever. The class watches a marble roll 6 meters and slow to a stop. How should the model be revised?

A class wants evidence that a cart's kinetic energy changed as it rolled down a ramp. Which pair of measurements gives that evidence most directly?

Hearing a loud bang when two moving carts crash is evidence that some of their kinetic energy was transferred to the surroundings.