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Pepsi [2]
3 years ago
14

A worker stands still on a roof sloped at an angle of 35° above the horizontal. He is prevented from slipping by static friction

al force of 560 N. Find the mass of the worker.

Physics
1 answer:
aleksley [76]3 years ago
5 0

Answer:

99.63 kg

Explanation:

From the force diagram

N = normal force on the worker from the surface of the roof

f = static frictional force = 560 N

θ = angle of the slope = 35

m = mass of the worker

W = weight of the worker = mg

W Cosθ = Component of the weight of worker perpendicular to the surface of roof

W Sinθ = Component of the weight of worker parallel to the surface of roof

From the force diagram, for the worker not to slip, force equation must be

W Sinθ = f

mg Sinθ = f

m (9.8) Sin35 = 560

m = 99.63 kg

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