An object with a mass of 20 kg is lifted by the arrangement shown in the diagram. Air resistance (drag) can be ignored, and the gravitational field strength (acceleration due to gravity) can be taken as 10 N/kg. What is the acceleration of the object, in m/s²?

Answer:

16) 2m/s²

Downward force (Weight of object) = 20 x 10 = 200N
Upward force = 120 + 120 = 240 N
Resultant force = 240-200 = 40 N

Force = mass x acceleration
40 = 20 x a
a = 40 ÷ 20 = 2 m/s²