Question

A flatbed truck is carrying a 20.0-kg crate along a level road. The coefficient of static friction between the crate and the bed is 0.400. What is the maximum acceleration that the truck can have if the crate is to stay in place? (A) 3.92 m/s2 (B) 7.84 m/s2 (C) 8.00 m/s2 (D) 78.5 m/s2 (E) 196 m/s2

Answer 1

Answer:

(A) 3.92 m/s²

Explanation:

From friction,

F = μR .................. Equation 1

Where F = Frictional force, μ = coefficient of static friction, R = Normal reaction.

But,

R = mg and

F = ma

therefore

ma = mgμ

Where a = acceleration, g = acceleration due to gravity, m = mass of the crate.

a = gμ...................... Equation 2

Given: μ = 0.4

Constant: g = 9.8 m/s

Substitute into equation 2

a = 0.4(9.8)

a = 3.92 m/s²

Hence the right option is (A) 3.92 m/s²

Answer 2

Explanation:

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