Exam Questions Flashcards
1
Q
In a vacuum, how is liquid kept hot?
A
Silver surface reduces heat lost by radiation
It is the best emitter
The vacuum reduces heat lost by convection
It doesn’t allow currents to form
The cap reduces heat loss by evaporation
It keeps the heat particles in
2
Q
How does the size of the ears of a fox help it to keep warm
A
Small surface area
Reduces heat radiated
3
Q
What is convection current?
A
Particles are heated and gain thermal energy
They move apart
Water becomes less dense
Hot water rises
4
Q
Advantage for hydroelectric energy
A
No fuel costs
Renewable
No harmful gases produced
5
Q
The amount of electricity used for lighting homes decreased in 2007. Why?
A
More people were becoming environmentally aware
