GCSE Questions: Forces

Q8. The diagram shows a boat floating on the sea. The boat is stationary.

(a) Here is part of the free body diagram for the boat.

(i) Complete the free body diagram for the boat.







[2 marks]

(ii) Calculate the mass of the boat given that the gravitational field strength = 9.8 N/kg.

Give your answer to two significant figures.

[4 marks]

(b) When the boat propeller pushes water backwards, the boat moves forwards. The force on the water causes an equal and opposite force to act on the boat.

Which law is this an example of?

[1 mark]

(c) The diagram below shows the boat towing a small dinghy.

The tension force in the tow rope causes a horizontal force forwards and a vertical force upwards on the dinghy.

horizontal force forwards = 150 N

vertical force upwards = 50 N

Here is a piece of graphpaper. Use it to draw a vector diagram, to scale, in order to determine the magnitude of the tension force in the tow rope, and the direction of the force this causes on the dinghy.

[4 marks]

[11 Marks TOTAL]