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3 years ago

2.

Physics

1 answer:

Alex_Xolod [135]3 years ago

5 0

Answer:

The work done on the sled by friction, W = - 4593.75 J

Explanation:

Given data,

The combined mass of sled and the boy, m = 75 kg

The displacement of the boy, S = 25 m

The coefficient of the friction, u = 0.25

The frictional force acting on the boy,

F = u η

Where,

η - is the normal force acting on the boy (mg)

Substituting the values,

F = 0.25 x 75 x 9.8

= 183.75 N

Since the direction of the frictional force is against the direction of motion

F = - 183.75 N

The work done on the sled by friction,

W = F x S

= - 183.75 x 25

= - 4593.75 J

Hence, the work done on the sled by friction, W = - 4593.75 J

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