Torque Review

Torque Review

Multiple Choice

Which hammer will produce more torque to pull a nail? (assume the same force applied)

• The longer hammer

• The shorter hammer

• They are the same

Explanation Slide...

The longer hammer handle is a longer torque arm.

Multiple Choice

Within the human body, which of these uses levers and torque to function?

• Arms

• Legs

• Head and neck

• All of them

Explanation Slide...

Multiple Choice

With a lever, anytime the torque arm length for the effort is increased, . . .

• more torque is produced so more can be lifted

• less torque is produced so less can be lifted

• less torque is produced so more can be lifted

• more torque is produced so less can be lifted

Explanation Slide...

Increasing the torque arm length for the effort gave the effort an advantage so now more can be lifted.

Multiple Choice

The effort force is supposed to be able to lift the load. While keeping the effort torque arm length the same, if the torque arm length for the load/resistance is increased, . . .

• either more effort force is needed or the load must be decreased

• either less effort force is needed or the load must be decreased

• either less effort force is needed or the load must be increased

• either more effort force is needed or the load must be increased

Explanation Slide...

Increasing the torque arm length for the load gave the load an advantage.

Multiple Choice

With the lever shown, what would happen to the force needed if the pivot was moved closer to the load?

• The force needed gets larger

• The force needed gets smaller

• The force needed doesn't change

Explanation Slide...

The load ends up with a shorter torque arm so it results in less torque resisting the effort force and torque. It is easier to lift the load - less effort force needed.

Multiple Choice

With the lever shown, what would happen to the force needed if the pivot was moved closer to the effort force?

• The force needed gets larger

• The force needed gets smaller

• The force needed doesn't change

Explanation Slide...

The effort force ends up with a shorter torque arm so more force is needed to give enough torque.

Multiple Choice

With the lever shown, what would happen to the force needed if the load was moved farther from the pivot?

• The force needed gets larger

• The force needed gets smaller

• The force needed doesn't change

Explanation Slide...

The load ends up with a longer torque arm so it results in more resistance (more torque) to what the effort force is trying to do.

Multiple Choice

With the lever shown, what would happen to the force needed if the load was moved closer to the pivot?

• The force needed gets larger

• The force needed gets smaller

• The force needed doesn't change

Explanation Slide...

The move shortens the torque arm length for the load so it produces less torque. This means that less force is needed to produce a balance.

Multiple Choice

With the lever shown, what would happen to the force needed if the force was moved farther from the pivot?

• The force needed gets larger

• The force needed gets smaller

• The force needed doesn't change

Explanation Slide...

The effort force ends up with a longer torque arm so less force is needed to keep the torques balanced.

Multiple Choice

When there is rotational equilibrium for levers, which statement is true?

• The torque from the weight of the load is greater than torque from the the force applied

• The torque from the force applied greater than the torque from the weight of the load

• The torques from the force applied and from the weight of the load are equal and balanced

Explanation Slide...

"Equilibrium" is like "Equal"

Multiple Choice

When the torques (from the load and force applied) are balanced, how do the weight of the load and the force applied compare to each other in this situation?

• The force applied is greater than the weight of the load

• The weight of the load is greater than the force applied

• The force applied and the weight of the load are equal or close to equal

Explanation Slide...

The force applied has a longer torque arm so the force applied must be less in order to balance the torque produced by the load.

Multiple Choice

When the torques (from the load and force applied) are balanced, how do the weight of the load and the force applied compare to each other in this situation?

• The force applied is greater than the weight of the load

• The weight of the load is greater than the force applied

• The force applied and the weight of the load are equal or close to equal

Explanation Slide...

The force applied has a longer torque arm so the force applied must be less in order to balance the torque produced by the load.

Multiple Choice

When the torques (from the load and force applied) are balanced, how do the weight of the load and the force applied compare to each other in this situation?

• The force applied is greater than the weight of the load

• The weight of the load is greater than the force applied

• The force applied and the weight of the load are equal or close to equal

Explanation Slide...

The force applied has a shorter torque arm so the force applied must be greater in order to get enough torque to balance the torque produced by the load.

Multiple Choice

If the load is the same in both situations, which one will require less force to lift the load

• Situation Y

• Situation X

• They require the same amount of force

Explanation Slide...

In X the effort force has a longer torque arm and the load has a shorter torque arm. They both mean that less force is needed.

Multiple Choice

Any time the torque arm length of the resistance is decreased (by moving the load), the amount of effort force needed will be ________.

• increased

• decreased

• unchanged

Explanation Slide...

Decreasing the torque arm length of the resistance gives it less ability to resist the effort. This means that the effort force must get smaller to balance it out.

Multiple Choice

Any time the torque arm length of the effort force is decreased, the amount of load (resistance) that can be lifted is ___________.

• increased

• decreased

• unchanged

Explanation Slide...

Decreasing the torque arm length of the effort force gives it less ability to put torque on the load so less weight can be lifted.

Multiple Choice

In the picture, the person's left hand is on the end of the handle and the right hand is in the middle area of the handle.

What would happen to the amount of force needed to lift the shovel if the right hand was moved closer to the scoop of snow?

• More force will be needed

• Less force will be needed

• The amount of force needed doesn't change

Explanation Slide...

This will make torque arm for the effort force longer. This will reduce the amount of force needed.

Multiple Choice

A car's transmission is designed to take the torque and speed from an engine and adjust them to deliver the torque and speed to the wheels

• That is TRUE

• That is FALSE

Explanation Slide...

Multiple Choice

What will happen to the torque and speed of a shaft connected to the middle of gear A? (Notice that the big gear drives the small gear.)

• Increased torque, increased speed

• Decreased torque, decreased speed

• Decreased torque, increased speed

• Increased torque, decreased speed

Explanation Slide...

A big one driving a small one will produce less torque but also more rotation (speed). More speed is usually the reason this is used.

Multiple Choice

What will happen to the torque and speed of a shaft connected to the middle of gear B? (Notice that the small gear drives the big gear.)

• Increased torque, increased speed

• Decreased torque, decreased speed

• Decreased torque, increased speed

• Increased torque, decreased speed

Explanation Slide...

A small one driving a big one will produce more torque but also less rotation (speed). This allows heavy things to be moved with the use of a smaller motor.

Multiple Choice

When pulleys, gears or sprockets are used, if torque is increased (because of sizes used), what happens to the speed produced in the other one?

• Speed is increased

• Speed is decreased

• Speed could be equal

Explanation Slide...

With torque and speed, if one goes up the other goes down.

Multiple Choice

When pulleys, gears or sprockets are used, if speed is increased (because of sizes used), what happens to the torque produced in the other one?

• Torque is increased

• Torque is decreased

• Torque could be equal

Explanation Slide...

With torque and speed, if one goes up the other goes down.

Multiple Choice

When a smaller gear drives a larger gear, the result in the larger gear is ____ torque and ____ speed.

• more torque and more speed

• more torque and less speed

• less torque and less speed

• less torque and more speed

Explanation Slide...

When the small gear goes around once, the larger one goes around less than once in the same amount of time. That makes for less speed in the shaft of the large one.

Multiple Choice

When a larger gear drives a smaller gear, the result in the smaller gear is ____ torque and ____ speed.

• more torque and more speed

• less torque and less speed

• more torque and less speed

• less torque and more speed

Explanation Slide...

When the large gear goes around once, the smaller one goes around more than once in the same amount of time. That makes for more speed in the shaft of the small one.