Kinetic energy, ke

3 marks · Easy

A book of mass 2 kg is resting on a shelf that is 4 m above the ground.

(a)

State the equation you would use to calculate the gravitational potential energy (GPE) of the book.

[1 mark]

(b)

Calculate the GPE of the book. Take .

[2 marks]

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(a) GPE = mgh

(b) 80 J

Common mistakes: Multiplying by weight instead of mass

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Marking points

B1 (a) · 1 mark · States or writes correct GPE equation.

M1 (b) · 1 mark · Substitutes values into equation correctly.

A1 (b) · 1 mark · Calculates correct GPE value.

Worked solution