Heat Homework Wk 4 – S1 Science Homework


In your jotter write the DATE in the margin. Now add a TITLE for your homework. Your title should be the name of the Homework: Heat Homework Wk 4

Question 1.

A white washed wall on a house absorbs 40% of heat radiation from the Sun and reflects 60% back into the atmosphere. Another wall on the same house made of red brick absorbs 70% and reflects back 30%. Tar, which is used for resurfacing roads, reflects 10% and absorbs 90%.

a) In your jotter, construct a table to show this information. Remember to include headings.

b) If the Earth absorbs 85% of heat radiation from the Sun, how much does it reflect back into space?

c) List the surfaces red brick wall, white washed wall, tar and Earth in order of how much they absorb heat.

d) On sunny days tar on the roads becomes soft. Explain why this happens.

Question 2.

A beaker was heated below the colured crystal as shown in the diagram. Which diagram shows how the colour will move?

Question 3.

The diagram below shows an electric fire.

a) On the diagram which of the labelled arrows is showing radiation?
b) Explain your choice.
c) Arrow A contributes to the heating of a room by the fire. What type of heat transfer is depicted by arrow A?

Question 4.

Sohail carried out an experiment to find out which type of surface absorbed heat best. He put some black and silver paper on the back of his hands and held them under a lamp as shown opposite.

a) Which hand becomes hottest first?

b) Why is it a fair test?

c) Copy and complete the following sentences.

Question 5.

Heat travels well by radiation through


	A.	wood
	B.	steel
	C.	a vacuum
	D.	aluminium

For questions 6 and 7 choose from the options listed below.

	A.	red
	B.	black
	C.	white
	D.	yellow

Question 6.

From what colour surface would the most heat be given out?

Question 7.

Through what colour surface is heat absorbed most by?

Question 8.

Heat travels well by radiation through……..



	A.	air
	B.	wood
	C.	iron
	D.	copper

For questions 9, 10, 11 and 12 choose your answer the options below.

	A.	conduction
	B.	convection
	C.	radiation

Question 9.

What form of heat transfer brings heat energy to the Earth from the sun?

Question 10.

When holding a snowball in your hand how does the heat flow from your hand?

Question 11.

How does heat get to the bread when making toast?

Question 12.

How does heat flow from the electric iron to your clothes when you are ironing?

Question 13.

Some coins were left out in the sunshine. Which of the coins would get hot the quickest?

Question 14.

Heat moves by convection currents in……..



	A.	air
	B.	iron
	C.	rubber
	D.	plastic

Question 15.

Saucepan handles are made of wood because……….



	A.	wood is an attractive material
	B.	wood is a poor conductor of heat, so doesn’t get hot
	C.	wood is a good conductor of heat, so doesn’t get hot
	D.	wood is cheap

Question 16.

Tar melts on the road on a very hot day because roads



	A.	are melted by the earth
	B.	radiate heat to the sun
	C.	absorb heat from the sun
	D.	conduct heat into the earth

Question 17.

Two identical cars, one white and one black were parked in the sun. After a few hours the metalwork of the dark one was hot to the touch, but the white one was not. This is because…….


	A.	dark paint retains the heat
	B.	white paint keeps the cold in
	C.	dark paint absorbs heat better than white
	D.	dark paint reflects heat better than white

Question 18.

Here are some statements about heat transfer. Which is correct?


	A.	Radiation only occurs in a vacuum
	B.	Radiation only occurs in a gas
	C.	Convection occurs in a vacuum
	D.	Convection only occurs in a liquid or a gas
	E.	Convection only occurs in a solid