The problem gives us the minimum force required to move the cabinet. That means the force Erin exerts will be equal to the force due to friction, but moving in the opposite direction. 

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From here, expand the right side using the formula for kinetic friction and normal force.

Use the given values for the force, mass, and acceleration of gravity to solve for the coefficient of friction.

The force due to friction on a level surface is the product of the normal force and the coefficient of friction:

We are told the force required to move the block, which will be equal to the force of friction, and the mass of the block. Use the mass of the block to calculate the normal force.

Use the normal force and the force of friction to solve for the coefficient of friction.

Kinetic friction is never greater than static friction. More force is always requires to overcome static friction than is required to overcome kinetic friction. It can require a large force to initiate motion, causing an initial acceleration by overcoming static friction. Once motion has begun, however, less for is required to maintain the motion due to the principles of Newton's first law and inertia.

Weight is a particular force that is equal to mass times acceleration due to gravity. Start with Newton's second law, .

Plug in the given values to solve.

Weight is a specific force. It is always equal to the mass times acceleration due to gravity:.

Plug in the given values to solve for the acceleration.

The gravitational acceleration is negative because it acts in the downward direction.

Weight is a specific force that is always equal to mass times acceleration due to gravity.

Start with Newton's second law: .

Plug in the given values to solve for the mass.

If the velocity on an object is constant, that means it has no acceleration. If it has no acceleration, that means that the net force on the object is equal to zero. We can see this conclusion by using Newton's second law.

Another way to think of  is the sum of all the forces. Since the only two forces acting upon the ball are gravity and Jerry's lifting force, we can see: .

Since the net force is zero, the magnitude of Jerry's force must equal the magnitude of the force of gravity, but in the opposite direction.

This means that once we find , then Jerry's lifting force will be the same magnitude but in the opposite direction. Use Newton's second law to find the force of gravity.

This means that Jerry's lifting force will be .

Mass is a measure of how much matter is in an object, while weight is a measurement of the effective force of gravity on the object.

The amount of matter in the astronaut does not change; therefore, she has the same mass on the moon as she has on Earth.

Her weight, however, will change due to the change in gravity. The force of gravity will be the product of the acceleration and the astronaut's mass.

If the gravity is less on the moon than on Earth, then the force of gravity on the astronaut will also be less on the moon; thus, she will weigh less.

W will be the weight of the object. Weight is a very specific force: it is the mass times gravity. As it turns out, the angle is irrelevant in finding weight.

Using Newton's second law and the given values for mass and gravity, we can solve for W.

Note that the weight is negative, because it is acting in the downward direction.

Weight is a very specific force, equal to the mass times gravity:

On this new planet her weight is half of what it was on Earth. We can write this mathematically, using the weight equation.

Mass cancels out from each side, leaving a relationship between the gravitational accelerations.

That means the acceleration due to gravity on this new planet is half of what it was on earth.