Physics

Question 1

Name three different energy stores?

Answer 1

Thermal, kinetic, gravitational potential, elastic potential, chemical, magnetic, electrostatic, and nuclear.

Question 2

Give three ways in which energy can be transferred?

Answer 2

Energy can be transferred mechanically (work is done by a force), electrically (work is done by moving charges), or by heating.

Question 3

What is meant by a ‘system’?

Answer 3

A system is an object or a group of objects.

Question 4

Which stores is energy transferred between when a car is slowed down by applying the brakes?

Answer 4

Energy is transferred from the kinetic energy store of the car to the thermal energy stores.

Question 5

Describe the energy transfers that take place when water is heated in an electric kettle. Name the energy stores that are involved.

Answer 5

Energy is transferred electrically to the thermal energy store of the kettle’s heating element, which transfers by heating.

Question 6

Smita throws a ball vertically upwards into the air. Describe and explain the energy transfers that occur from the moment the ball is released up to the highest point on its path. Assume that air resistance acts on the ball during flight.

Answer 6

Energy is transferred from the kinetic energy store of the ball to its gravitational potential energy store. Energy is also transferred from the ball’s kinetic to thermal energy stores of the ball and the air as work is done by air resistance to slow down.

Question 7

when an object slows down, which store is energy being transferred away from?

Answer 7

the object’s kinetic energy store.

Question 8

A 2kg block and a 5kg block are both lifted to the same height.which block had more energy in its gravitational potential energy store?

Answer 8

the 5kg has more energy in its g.p.e store. {its got a higher mass and the amount of energy in its g.p.e store depends on mass as E= M x G.P.E x H.}