Mechanical Advantage of Levers

In a simple machine, what is the load?

• point where the lever arm pivots

• the force needed to move the load

• the weight lifted by a machine

• the distance the load travels

What is the point where the lever arm pivots?

• load

• fulcrum

• mass

• effort

What class lever is pictured below?

• Class-1 &3

• Class-3

• Class-2

• Class-1

Tags

NGSS.MS-PS2-1

NGSS.MS-PS2-2

The amount by which a machine multiplies input force is known as the 

• work.
• power.
• output force.
• mechanical advantage.

To lift a load off the ground, the force required is equal to the weight of the load. In the case of a lever, however, a small effort force can be used to lift a much heavier load. How is this possible?

• Levers use the weight of the load combined with the effort to lift the load.

• Levers combine the weight of the load with the force of gravity to lift the load.

• Levers reduce the force required by increasing the distance over which the force is applied.

• Levers distribute the load over their length, thereby reducing the force required to lift the load.

What is the mechanical advantage of a lever that has an effort arm of 20 meters and a resistance arm of 4 meters?

• 4

• 5

• 80

• .2

Using a lever, Joe is able to lift a 15,000 N SUV off of the ground with a force of 3000 N. What is the mechanical advantage of the lever?

• 1

• 5

• 45

• .2

You need to lift a 500 N box off the ground. What is the effort required to lift the box off the ground using a 10 m long lever? The fulcrum is placed 2 m from the box. *Tip: You will need to use two formulas.

• 5 N

• 125 N

• 50 N

• 80 N

What is effort (input) force?

• the force one exerts on a machine

• the force which an effort force must overcome in order to do work on an object via a simple machine.

• the force the machine exerts on a object

• the output work times the input distance

What is the output force?

• the force required by a machine in order to accomplish work (the force you put on the machine)

• The force that is exerted by a machine

• the force the object exerts on a machine

• the output work times the input distance