Fig. Shows a brake shoe applied to a drum by a lever ab which is pivoted at a fixed point a and rigidly fixed to the shoe. The radius of the drum is 160mm. The coefficient of friction at the brake lining is 0.3. If the drum rotates clockwise, find the braking torque due to the horizontal force of 600n at b.
To find the braking torque due to the horizontal force at point B, we need to calculate the moment of this force.
First, let's determine the lever arm, which is the perpendicular distance between the point of rotation (point A) and the line of action of the force at B.
Looking at the provided figure, the lever arm is not explicitly mentioned. However, we can assume that it is the distance between point A and point B (as the lever is rigidly fixed to the shoe). Let's call this distance "r".
Given that the radius of the drum (r) is 160 mm, we need to convert it to meters to maintain consistency with other measurements. 1 meter is equivalent to 1000 mm, so:
r = 160 mm = 160/1000 m = 0.16 m
Now, we can calculate the braking torque (τ) using the formula:
τ = Force (F) * Lever Arm (r)
The force acting at B is given as 600 N. Substituting the values into the formula, we get:
τ = 600 N * 0.16 m
τ = 96 N*m
Therefore, the braking torque due to the horizontal force of 600 N at B is 96 N*m.