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WorksheetsRadiation (G9-ARIS)
Total questions: 12
Worksheet time: 15mins
Two metal cans are identical, except that one has a shiny silver outer surface and the other has a dull black outer surface. They each have 300 g of water at 80 °C sealed inside them. They are both in a vacuum, in the darkness of outer space.
How does the temperature of the water in each one change?
Neither one will cool down.
The water in the black can cools more slowly than that in the shiny can.
The water in the shiny can cools more slowly than that in the black can.
They both cool down at the same rate.
Vacuum flasks usually have silvered walls that help to keep the contents of the flask hot.
Why are the walls silvered?
to absorb thermal energy from the air around the flask
to increase the rate of convection inside the flask
to reduce energy loss to the surroundings by conduction
to reflect thermal radiation back into the flask
On a cold day, a shiny metal rod feels colder to the touch than a black plastic rod.
Which statement explains this observation?
The metal rod is a better absorber of infra-red radiation than the plastic rod.
The metal rod is a better thermal conductor than the plastic rod.
The metal rod is a worse absorber of infra-red radiation than the plastic rod.
The metal rod is a worse thermal conductor than the plastic rod.
Which statement about infra-red radiation is correct?
A black surface is a poor absorber of infra-red radiation.
A dull surface is a better emitter of infra-red radiation than a shiny surface.
A shiny surface is a better absorber of infra-red radiation than a dull surface.
A white surface is a poor reflector of infra-red radiation.
Which statement about thermal radiation is correct?
It can only occur in a vacuum.
It involves movement of electrons through a material.
It involves movement of atoms.
It is infra-red radiation.
Two methods by which thermal energy can be transferred are conduction and radiation. Which statement is correct?
Conduction involves density changes in fluids.
Conduction only occurs in solids.
Radiation cannot occur in a vacuum.
Radiation involves electromagnetic waves.
What is the name of the process f heat transfer using electromagnetic waves?
conduction
convection
evaporation
radiation
The diagram shows a vacuum flask used to keep liquid hot.
How does thermal energy pass through the vacuum?
conduction only
convection only
radiation
conduction and convection
A heating engineer fits a heater to the ceiling of an office so that workers in the office are kept warm.
How does thermal energy reach the workers below the heater?
conduction and convection
convection and radiation
convection only
radiation only
The diagram shows the cross-section of a vacuum flask containing a hot liquid in a cold room.
X and Y are points on the inside surfaces of the walls of the flask.
How is thermal energy transferred between X and Y?
by conduction and convection
by conduction only
by radiation and convection
by radiation only
Fig. 4.1 shows a solar water-heating panel on the roof of a house.
Cold water flows into the copper tubes, which are heated by solar radiation. Hot water flows out of the tubes and is stored in a tank.
Explain why the tubes are made of copper and are painted black.
Write down another name for heat radiation.
