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A 5.0 kg block is placed on a 30 degree inclined plane and held in place. A string is attached to the block which goes over the pulley at the top of the plane and is attached to a hanging mass. The mechanism holding the block in place is released and the block does not move. The coefficient of friction between the block and the plane is 0.23.

What is the range (minimum to maximum) of mass that the hanging mass could be and still prevent the block from sliding?

User Mivaweb
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Answer:

Therefore, the value of M is approximately 0.503 m/s^2.

Step-by-step explanation:

To determine the range of mass that the hanging mass could be and still prevent the block from sliding, we need to consider the forces acting on the block.

The weight acting vertically downward can be resolved into two components: one parallel to the inclined plane (mg*sinθ) and one perpendicular to the inclined plane (mg*cosθ). Here, m is the mass of the block and θ is the angle of inclination.

The force due to friction acting on the block is given by the coefficient of friction (μ) multiplied by the normal force (mg*cosθ).

Since the block is in equilibrium and not moving, the force pulling the block down (mg*sinθ) must be balanced by the sum of the frictional force and the tension in the string.

Let's denote the mass hanging from the string as M.

So, the equation for the equilibrium condition is (mg*sinθ) = (μ * mg*cosθ) + (M * g).

Now, we can solve for M to determine the range of masses that would prevent the block from sliding.

Rearranging the equation, we get:

M = (mg*sinθ - μ * mg*cosθ) / g.

Plugging in the given values, we have:

M = (5.0 kg * 9.8 m/s^2 * sin(30°) - 0.23 * 5.0 kg * 9.8 m/s^2 * cos(30°)) / 9.8 m/s^2.

Calculating this expression gives us the range of masses M that would prevent the block from sliding. Let's calculate the expression:

M = (5.0 kg * 9.8 m/s^2 * sin(30°) - 0.23 * 5.0 kg * 9.8 m/s^2 * cos(30°)) / 9.8 m/s^2

To simplify further, let's calculate the values of sin(30°) and cos(30°):

sin(30°) = 0.5

cos(30°) = √3/2

Now, substitute these values back into the equation:

M = (5.0 kg * 9.8 m/s^2 * 0.5 - 0.23 * 5.0 kg * 9.8 m/s^2 * √3/2) / 9.8 m/s^2

Simplifying further:

M = (49 N * 0.5 - 0.23 * 49 N * √3/2) / 9.8 m/s^2

M = (24.5 N - 0.23 * 49 N * √3/2) / 9.8 m/s^2

M = (24.5 N - 11.305 N * √3) / 9.8 m/s^2

Calculating the final value:

M ≈ (24.5 N - 19.572 N) / 9.8 m/s^2

M ≈ 4.928 N / 9.8 m/s^2

M ≈ 0.503 m/s^2

User Pwaterz
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