Answer:
a) 0.1m/s^2 b) 0.12m/s^2
Explanation:
a) Using the concept of friction to solve the question,
First we need to know all the forces acting on the body on the inclined plane
Forces acting parallel to the plane are the moving force (Fm), frictional force(Ff) and mgsintheta (resolving weight along the plane).
Force acting perpendicular to the plane are weight (mgcostheta) and the normal reaction.
Using the formula
Summation of forces along the plane = mass × acceleration
Fm+mgsintheta -Ff= ma...(1)
Fm= 7.0N
Mass= 1.0kg
Ff=0 (since the movement is frictionless)
Substituting the datas in (1)
7.0 + 1×10sin20-0 = 1.0a
7.0+3.42=1.0a
a = 1.0/10.42
a= 0.1m/s^2
b) Now that the fictional force is 1.9N, the acceleration will change. Using the same formula in (a)
7.0+1×10sin20-1.9 = 1.0a
7.0+3.42-1.9=1.0a
8.52 = 1.0a
a = 1.0/8.52
a=0.12m/d^2
