Heat and Thermodynamics Execises (1)

Rudra pours hot tea into a cup for his breakfast and places the cup on a table in the kitchen. Which describes the possible ways heat would be transferred in the system?

Choose 3 answers

• Heat transfers from the cup to the air

• Heat transfer from the air to the cup

• Heat transfers from the tea to the cup

• Heat transfers from the tea to the air

Sammie has a pile of identical stepping stones that have been warmed in the sun on a hot day. She places three stones in a cold stream to create a path for crossing. The stones are not touching each other.

Which describes the possible ways heat would be transferred in this system. Choose 2 answers.

• Heat transfer from the water in the stream to the stones.

• Heat transfer from the stones to the water in the stream.

• Heat transfer from the air to the water in the stream.

• Heat transfer between the stones.

Nikola brings in a blanket from his room and places it on a sofa in the living room. The air in the living room is slightly warmer than the blanket. Which temperature changes will occur in the system? Choose 2.

• The room's air will get warmer because heat flows into it from the blanket.

• The room's air will get cooler because heat flows from it to the blanket.

• The blanket will get warmer because heat flows into it from the room's air.

• The blanket will get cooler because heat flows from it to the room's air.

A family is packing for a picnic. They put two 0⁰C cold packs, several 27⁰C soda cans, and two 10⁰C salad containers from the refrigerator into an isolated bag. Which correctly describes how thermal energy will be transferred?

• The container of salad and the soda cans transfers thermal energy to the cold packs.

• The container of salad transfers thermal energy to the soda cans and the cold packs

• The cold packs transfer thermal energy to the containers of salad and the soda cans

• The cold packs and the soda cans transfer thermal energy to the containers of salad

A half-full bottle containing 1 kg of water at 5⁰C and full bottle containing 2 kg of water at an unknown temperature are placed in an insulated bag. Upon reaching thermal equilibrium, the half-full bottle's temperature increases to 20⁰C. The specific heat of the water is 4.18 kJ/Kg^oC. Assume that the system is thermally isolated. Which statement is CORRECT?

• The half-full bottle lost 62.7 kJ of thermal energy, and the full bottle gained 125.4 kJ of thermal energy.

• The half-full bottle lost 62.7 kJ of thermal energy, and the full bottle gained 62.7 kJ of thermal energy.

• The half-full bottle gained 62.7 kJ of thermal energy, and the full bottle lost 125.4 kJ of thermal energy.

• The half-full bottle gained 62.7 kJ of thermal energy, and the full bottle lost 62.7 kJ of thermal energy.