Question

4. a metal cylinder of height 4.5 cm and base area 24 cm2.
metal cylinder 4.5 cm

The density of the metal is 7900 kg m–3.
(a) Show that the mass of the cylinder is 0.85 kg.

(b) The cylinder is placed on a plank

The plank is at an angle of 40° to the horizontal
Calculate the pressure on the plank due to the cylinder.
pressure = .................................................... Pa [3]
(c) The cylinder then slides down the plank with a constant acceleration of 3.8 m s–2.
A constant frictional force f acts on the cylinder.
Calculate the frictional force f.
f = ...................................................... N [3]

Please explain the answer.