Answer:
Angle of inclination = 16.7°; normal reaction = 93.96N
Step-by-step explanation:
Frictional force is known as force of opposition that tends to oppose the motion of a body (moving force Fm) placed on a rough surface. Frictional force Ff is expressed as;
Ff = nR where;
n is the coefficient of static friction
R is the normal reaction
From the formula;
n = Ff/R
Where Ff = Fm = Weight of the object × sinθ i.e Wsinθ
and R = Wcosθ
n = wsinθ/wcosθ
n = sinθ/cosθ
n = tanθ
Given µs = 0.3
0.3 = tanθ
θ = arctan0.3
θ = 16.7°
Angle of inclination is 16.7°
The normal reaction at B if the ladder is on the verge of slipping can be gotten using the expression;
R = wcosθ
R = mgcosθ where
m is the mass of the ladder = 10kg
g is the acceleration due to gravity = 9.81m/s
R = 10×9.81×cos16.7°
R = 93.96N