Question 78
A particle A A\,A of mass 2 kg lies on a rough plane inclined at 40° 40°\,40° to the horizontal. It is connected by a light inextensible string, passing over a smooth pulley, to a particle B B\,B of mass 3 kg which hangs vertically. The string is parallel to a line of greatest slope of the plane, and its tension is 23.4 N.
Take i\mathbf{i}i horizontally to the right and j\mathbf{j}j vertically upwards.
a.[3]
Find the force exerted by the string on the pulley in component form.
b.[3]
Find the magnitude and direction of this force.
c.[1]
The pulley is in equilibrium. State the force that its support must exert on it.