Answer:
a. 10.2 N b. 1.73 c. 58.8 N d. 10.2 N
Step-by-step explanation:
a. The force that will make the block slide down the plane
This is the component of the block's weight along the plane F = mgsinθ where m = mass of block = 1.2 kg, g = 9.8 m/s² and θ = angle of incline = 60°.
So, F = mgsinθ = 1.2 kg × 9.8 m/s² × sin60°.= 10.18 N ≅ 10.2 N
b. The coefficient of friction
The coefficient of friction, μ = tanθ = tan60° = 1.73
c. The normal reaction.
This is equal to the vertical component of the block's weight. So, F = mgcosθ. Substituting the values for the variables from above, we have
F = mgcosθ = 1.2 kg × 9.8 m/s² × cos60°.= 58.8 N
d. The frictional force
Since the block does not slide, there is no net force on it. If f is the frictional force, then
F - f = ma. Since a = acceleration = 0,
F - f = 0
f = F = mgsinθ = 1.2 kg × 9.8 m/s² × sin60°.= 10.18 N ≅ 10.2 N