- #1

Jamest39

- 34

- 1

## Homework Statement

The two blocks are moving rightward at a constant speed along their inclined surfaces. The coefficient of kinetic friction is the same for both blocks. a) Determine the coefficient of kinetic friction. b) Determine the tension in the cord that connects the blocks to one another.

M=4kg; m=5kg; θ_1=28°; θ_2=36°

## Homework Equations

∑F = ma

kinetic friction = μN

## The Attempt at a Solution

Let N_1 = normal force of block M; N_2 = normal force of block m; f_1 = kinetic friction of block M; f_2 = kinetic friction of block m.

For block M:

∑Fy = M*0 = (N_1) - M * g * cos(θ_1) ⇒ N_1 = M * g * cos(θ_1)

ΣFx = M * a = T - (f_1) - M * g * sin(θ_1)

For block m:

ΣFy = m*0 = (N_2) - m * g * cos(θ_2) ⇒ N_2 = m * g * cos(θ_2)

ΣFx = m * a = (f_2) - T + m * g * sin (θ_2)

f_1 = μ * M * g * cos(θ_1)

f_2 = μ * m * g * cos(θ_2)

Since the acceleration, the kinetic friction forces, the coefficient of kinetic friction, and tension are all unknown, I couldn't come up with any way to isolate any of those values to solve for it.