Skip to content

Course home

Sign up

8 Energy – forces doing work

EasyMediumHard
123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110
Question 58
H

A winch is used to pull a box up a ramp onto the back of a lorry.

The Figure shows the box on the ramp.

Figure

image

The winch pulls the box up the whole length of the ramp with a constant force of 250 N parallel to the ramp.

The mass of the box is 40 kg.

The winch motor is supplied with 3000 J of energy as the box is pulled up the ramp.

Gravitational field strength (ggg) = 10 N/kg

a.

Calculate the work done by the winch on the box.

[2]
b.

Calculate the increase in gravitational potential energy of the box.

[2]
c.

Calculate the efficiency of the winch motor.

[2]
d.

Explain why the overall efficiency of raising the box, from the energy supplied to the winch motor to the gravitational potential energy store of the box, is lower than the efficiency of the winch motor.

Use your answers to (a), (b) and (c).

[3]
Markscheme

8 Energy – forces doing work Questions

  1. GCSE
  2. /Physics
  3. /8 Energy – forces doing work

Question bank