Question

A mass slides down an incline ((30 degree), with respect to the horizontal) with frictional constant 0.15. the mass weighs 10 kg. find its acceleration and equations of motion.

Answer 1

given:

mass=m=10 kg

angle of the incline=theta=30 degrees

friction coefficient=mu=0.15

forces acting on the mass are:

1. component of weight along the incline=m*g*sin(theta)

2. component of weight perpendicular to the incline=m*g*cos(theta)

3. friction force, in opposite direction of motion=mu*normal force=mu*m*g*cos(theta)

so total force along the incline=m*g*sin(theta)-mu*m*g*cos(theta)

acceleration=total force/mass

=g*sin(theta)-mu*g*cos(theta)

=3.6269 m/s^2