Bennett Mechanical Test Pulleys and Levers 4

Question 1

A crowbar used to pry up a board with the curved end resting on the ground is which lever class?

Accepted Answer

First-class lever

Answer

Second-class lever

Answer

Third-class lever

Answer

Wheel and axle

Question 2

A movable pulley system reduces the lifting force to one-third. How many rope segments support the load?

Accepted Answer

3

Answer

1

Answer

2

Answer

6

Question 3

Using a 6 ft lever with the fulcrum 1 ft from the load, what is the maximum mechanical advantage?

Accepted Answer

5

Answer

6

Answer

1

Answer

0.2

Question 4

A pair of tweezers used to grip a small object is which lever class?

Accepted Answer

Third-class lever

Answer

First-class lever

Answer

Second-class lever

Answer

Pulley

Question 5

Why does a single fixed pulley have a mechanical advantage of 1?

Accepted Answer

Only one rope segment supports the load

Answer

It uses no rope

Answer

It has two movable wheels

Answer

It reverses gravity

Question 6

Two children balance a seesaw. The heavier child should sit:

Accepted Answer

Closer to the fulcrum

Answer

Farther from the fulcrum

Answer

At the very end

Answer

Directly on the pivot

Question 7

An effort of 25 lb lifts a 150 lb load using a pulley system. What is the mechanical advantage?

Accepted Answer

6

Answer

5

Answer

3

Answer

125