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A mass m slides upward along a rough plane surface inclined at an angle of 0.23 radians to the horizontal. Initially, the mass has a speed of 4.77 m/s before it slides a distance of 1.0 m up the incline. After sliding this distance, the new speed of the mass is _______ m/s. What is the coefficient of kinetic friction between the mass and the incline?

User SamHoque
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Final answer:

The new speed of the mass after sliding up the incline can be found using the work-energy principle. The coefficient of kinetic friction can be calculated using the force of friction and the normal force.

Step-by-step explanation:

First, let's find the new speed of the mass after sliding up the incline. We can use the work-energy principle, which states that the work done on an object is equal to the change in its kinetic energy.

Since the work done by the frictional force is equal to the change in kinetic energy, we can write the equation:

Work done by frictional force = change in kinetic energy

The work done by the frictional force is equal to the force of friction multiplied by the distance the mass slides up the incline:

Work done by frictional force = force of friction * distance

The force of friction can be calculated using the equation:

Force of friction = coefficient of kinetic friction * normal force

In this case, the normal force is equal to the weight of the mass multiplied by the cosine of the angle of the incline:

Normal force = weight * cos(angle)

Finally, we can substitute these equations into the original equation to find the new speed of the mass:

force of friction * distance = 0.5 * mass * (final velocity^2 - initial velocity^2)

Solving for the final velocity, we get:

final velocity = sqrt((2 * force of friction * distance) / mass + initial velocity^2)

Plugging in the values for the force of friction, distance, mass, and initial velocity from the problem, we can calculate the final velocity.

To find the coefficient of kinetic friction, we can use the equation:

coefficient of kinetic friction = force of friction / normal force

Plugging in the values for the force of friction and normal force, we can calculate the coefficient of kinetic friction.

User TraneHead
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