OAR OAR Mechanical Comprehension: Simple Machines Questions and Answers 2

Question 1

A worker uses a wheel and axle to lift a bucket from a well. If the wheel has a radius of 30 cm and the axle has a radius of 5 cm, what is the mechanical advantage of this system?

Accepted Answer

6

Answer

5

Answer

3

Answer

10

Question 2

Which simple machine is represented by a doorstop being pushed under a door?

Accepted Answer

Wedge

Answer

Inclined plane

Answer

Lever

Answer

Screw

Question 3

A screw has 8 threads per inch. What is the pitch of this screw?

Accepted Answer

1/8 inch

Answer

8 inches

Answer

1/4 inch

Answer

1/2 inch

Question 4

A 200-lb crate is pushed up a 10-foot ramp to a loading dock 4 feet high. Ignoring friction, how much force is required to push the crate up the ramp?

Accepted Answer

80 lb

Answer

100 lb

Answer

50 lb

Answer

200 lb

Question 5

In a compound pulley system with 4 supporting ropes, how much effort is ideally needed to lift a 240-lb load?

Accepted Answer

60 lb

Answer

80 lb

Answer

120 lb

Answer

48 lb

Question 6

A first-class lever has the fulcrum placed 2 feet from the load and 6 feet from the effort. If the load weighs 150 lb, what effort is needed to balance the lever?

Accepted Answer

50 lb

Answer

75 lb

Answer

100 lb

Answer

25 lb