In this question use g=9.8g = 9.8g=9.8 m s−2^{-2}−2
A woman of mass 60 kg stands on a set of scales on the floor of a lift.
The scales give a reading equal to the magnitude, in newtons, of the normal reaction force between the woman and the scales.
At one instant during the journey the scales read 528 N. Find the magnitude and direction of the acceleration of the lift at that instant.
As the lift comes to rest at the end of a downwards journey, the scales read 678 N. Find the magnitude of the deceleration of the lift.
Explain why the scales read 588 N while the lift is descending at a constant speed.
139 exam-style questions on AQA A Level Maths 3.3 R: Forces and Newton's laws, covering 3.3.1 Concept of a force and Newton's first law, 3.3.2 Newton's second law, 3.3.3 Weight and motion under gravity, 3.3.4 Newton's third law and equilibrium, 3.3.5 Addition of forces and resultants (A-level only), and 3.3.6 Friction (A-level only). Each one has a worked solution and a mark scheme showing where the marks go.