PLZ HELP FAST Question 1 (3 points)

Which is an example of gravitational potential energy only?

Question 1 options:

An elevator moving up to the 3rd floor.

A skateboard rolling down a hill.

A puppy walking in circles under a tree.

An apple resting on the teacher's desk.

Question 2 (3 points)

How can you increase the gravitational potential energy (GPE) of an empty shoe box on the middle shelf of a bookcase?

Question 2 options:

Add items to the box to increase its mass.

Add items to the box and raise it to a higher shelf.

All options listed here will increase the GPE.

Raise the box to a higher shelf.

Question 3 (3 points)

Imagine two young children waiting to go down a slide. The first child goes down and then stays sitting at the bottom of the slide. If there is no friction involved and all of the mechanical energy is conserved what would happen to energy of the second child from the top to the bottom of the slide?

Question 3 options:

The energy is destroyed

Kinetic energy would turn into potential energy at the bottom.

All energy stays the same, it does not change

Potential energy from the top of the slide would turn to kinetic energy as they slide down. Then the kinetic energy of the child coming down the slide will be given to their sibling if they collide at the bottom.

Question 4 (3 points)

A 2-kg bowling ball sits on top of a building that is 40 meters tall. It falls toward the ground. Think about the amount of kinetic energy the bowling ball has as it falls. When would the ball have the most kinetic energy?

Question 4 options:

After it hits the ground and is no longer moving.

Just before it hits the ground and has reached a speed of 28 meters per second.

As it sits on top of the building

When it is half way between the top of the building and the ground, and has reached a speed of 19.8 meters per second.

Question 5 (3 points)

Changing which factor would NOT have an influence on the kinetic energy of a moving shopping cart?

Question 5 options:

Decreasing the mass or speed of the shopping cart.

Increasing the rate of speed you are pushing the shopping cart.

Increasing the mass of the cart by adding items.

Turning a different direction while moving the same speed.

Question 6 (3 points)

Which is an example of an object increasing its kinetic energy?

Question 6 options:

A jogger going faster after spotting a mountain lion behind him on the trail.

A rocket resting in the docking claps just before the launch sequence begins.

A train that has come to a complete stop so passengers can board the train.

An airplane after parking at the gate on the runway.

Question 7 (3 points)

In lesson 4.08, the skateboarder in the halfpipe and the pendulum animations provided a graphic illustration for how PE and KE changed. Why did the bar for the total energy remain constant?

Question 7 options:

Because energy is converted from KE to PE and PE to KE, but the total amount of energy is conserved.

Because these models do not take friction or air resistance into account.

All answers given are correct

Because no energy is being created or destroyed in this system.

Question 8 (3 points)

When is your kinetic energy the least when swinging on a park swing?

Question 8 options:

When at the lowest point or the bottom of the swinging path.

When halfway between the highest point of the swinging path and the bottom or lowest point in the path.

At the top of the swinging path, when you are still for a moment just before falling again.

When moving past the bottom of the path and going back up to the highest point.

Question 9 (3 points)

Mechanical energy is defined as

Question 9 options:

Energy of machines and tools

The energy of motion and position, represented by the formula: KE + PE = ME

Potential energy

Energy of motion

Question 10 (3 points)

Conservation of mechanical energy is defined as

Question 10 options:

Energy of motion

Potential energy added to kinetic energy

Law of conservation of energy

The sum of the kinetic and potential energies of an object remain a constant value unless there are forces acting on the object that cause a loss of energy overall, such a friction and air resistance.