Unit 2: Energy Transfer Technologies Test Review

  1. There are three methods of heat transfer: conduction, convection, and radiation.

a)Which method can occur only in liquids and gases?

b)Which method can occur only if there is contact between two surfaces?

c)Which method can occur in a vacuum or in outer space?

  1. A hot object is in contact with a cooler object.

a)Does thermal energy flow from the hot object to the cooler object?

b)Explain your answer.

  1. As you stand in front of a bonfire, the flames warm you. Use what you have learned about heat transfer to explain:

a)Why the part of your body facing the fire is warmer than the part facing away.

b)Why the flames and smoke rise.

  1. The city of Winnipeg is located near Lake Winnipeg, a large lake.

Why does Winnipeg not experience much of a drop in temperature at the end of a hot day?

  1. List the steps that produce a sea breeze.
  1. On a hot day, which place would be cooler? Explain why you think so.

a)A beach beside a large lake

b)20km away from the lake.

  1. List the transfers of energy involved in boiling water in a pot. Describe each transfer.
  1. Explain how three kinds of energy transfer are used in an oven when you bake bread.
  1. What is the difference between temperature and thermal energy.
  1. A boat in a harbor on a hot sunny day has a flag hanging from the mast. In what direction will the flag blow after sunset?
  1. Look at the identical objects below. In which object is the average kinetic energy of the particles greater? Explain your reasoning.

A: 45 degrees B: 50 degrees

  1. Look at the objects below. Do their particles have the same average kinetic energy? Which object has more thermal energy/heat? Explain your reasoning.

A: 80 degrees B: 80 degrees

  1. What is an insulator?
  1. What is a R-value? Substance A has a R-value of 5 and Substance B has a R-value of 10 which one is a better insulator?
  1. What is work? What is a force? Units?
  1. What are the simple machine we learned about? Sketch a picture of each.
  1. What is the difference between a fixed pulley and a moveable pulley?
  1. What is a kilowatt hours (kWh)
  1. What is the difference between renewable and non-renewable energy? Give 2 examples of each.
  1. What is efficiency?
  1. Calculate work being done. Nick picks up his toothbrush that has a weight of 2 N and lifts the toothbrush a vertical distance of 0.3 m. Calculate the work Nick did.
  1. The steering wheel of a large truck is usually larger than the steering wheel of a small car. Explain why the large truck might have a larger steering wheel than a small car.