Unit 1 Science

Which force produces energy as heat?

• pull

• gravity

• friction

• magnetic

Why do two surfaces get warm when they are rubbed together?

• The surfaces absorb energy from the air.

• Friction changes energy of motion to heat energy.

• Moving objects produce heat energy.

• Energy is transferred between the two surfaces.

Peter pushed a heavy box of books across his bedroom floor. The bottom of the box felt warm when he picked it up. What is the MOST likely reason the bottom of the box felt warm?

• Sunlight warmed the box before Peter pushed it.

• The box absorbed heat from the floor as it slid across it.

• Friction between the box and the floor made the box warm.

• The mass of the books pushed the box too hard against the floor

Cara was rubbing lotion on her hands. At first her hands stayed cool. But her skin began to get warm as it absorbed the lotion. What is the MOST likely reason Cara’s hands stayed cool while there was lotion between them?

• The lotion increased the friction between her hands.

• The lotion decreased the friction between her hands.

• The lotion contained ingredients that cooled her skin.

• The lotion contained ingredients that warmed her skin.

Anna is holding an ice cube. Why does the ice cube melt in her hand?

• Heat moves from her hand to the ice cube.

• Cold moves from her hand to the ice cube.

• Heat moves from the ice cube to her hand.

• Cold moves from the ice cube to her hand.

Jose used a metal spoon to stir a pot of hot soup.

How was the heat transferred from the soup to the spoon handle?

• by air movement

• by energy waves

• by contact between metal particles

• by contact between the soup and the handle

Michael placed a metal spoon in a cup of hot chocolate. At first the spoon handle felt cool. A few minutes later, it felt warm. What is the MOST likely reason the handle got warm?

• Heat transferred from the edge of the cup to the spoon.

• Heat transferred directly from the hot drink to the spoon handle.

• Heat transferred from the air around the mug to the spoon handle.

• Heat transferred from the hot drink to the spoon and then through the spoon.

The table lists the temperature of four objects.

How can heat transfer between objects?

• from 1 to 3

• from 2 to 4

• from 3 to 2

• from 1 to 4

Which action would show that air has mass and volume?

• jumping in a pool of water and letting your body dry in the wind

• watching the wind move a sailboat across a lake

• pulling an open plastic bag through the air and then closing it

• filling a bowl with hot water and then setting it outside in cool air

The picture shows a soccer ball.

The soccer ball has the shape shown because it is MOST likely

• in motion.

• filled with air.

• formed by gravity.

• stretched by rubber bands.