The coefficient of friction for an object sliding across a rough floor is 0.7. A 125 N horizontal force causes the object to accelerate at 1.2 m/s2 . What is the objects weight

152 N

Explanation:

From the question,

F-F' = ma Equation 1

Where F = Horizontal force, F' = Frictional force, m = mass of the object, a = accleration of the object.

But,

F' = mgμ Equation 2

Where g = acceleration due to gravity, μ = coefficient of friction.

make m the subject of the equation

Substitute equation 2 into equation 1

F-mgμ = ma.

make m the subject of the equation

m = F/(gμ+a) Equation 3

Given: F = 125 N, g = 9.8 m/s², μ = 0.7, a = 1.2 m/s²

Substitute these value into equation 3

m = 125/[(9.8×0.7)+1.2)

m = 125/8.06

m = 15.51 kg.

But,

W = mg Equation 4

Where W = weight of the object.

W = 15.51(9.8)

W = 152 N

about 45° and at the middel