Question

TOY
III. Answer in detail
1. The diagram shows a man pulling a child on the sledge The acceleration of the sledge is 1.5 m/s. The
mass of the child and the sledge is 38 kg,
(1) State the equation linking force, mass and acceleration
(II) Calculate the force needed to produce this acceleration
(III) Suggest a reason why the force exerted on the sledge
by the man must be greater than the force calculated,​

Answer 1

Given:

Acceleration of the sledge = 1.5 m/s²

Mass of the child + sledge= 38 kg

To find:

1. State the equation linking force, mass and acceleration
2. Calculate the force needed to produce this acceleration
3. Suggest a reason why the force exerted on the sledge  by the man must be greater than the force calculated,.

Solution:

• As we know that Force = mass× acceleration

Therefore the equation linking mass and acceleration is F = m × a.

• The force needed to produce this acceleration:

F = m× a

F = 38× 1.5

F = 57 N

Therefore the force needed to produce an acceleration of 1.5 m/s² is 57N.

• The force exerted on the sledge by the man must be greater than the force calculated because the friction between the sledge and ground will produce some resistive force, therefore more force will be required to overcome it.