OAR OAR Mechanical Comprehension: Simple Machines 2

Question 1

A wheel and axle consists of a large wheel attached to a smaller axle. If the wheel radius is 30 cm and the axle radius is 5 cm, what is the mechanical advantage?

Accepted Answer

6

Answer

Mechanical advantage of a wheel and axle = wheel radius / axle radius = 30 / 5 = 6.

Question 2

A wedge is used to split a log. If you double the length of the wedge while keeping the same width, what happens to its mechanical advantage?

Accepted Answer

It doubles

Answer

Mechanical advantage of a wedge = length / width, so doubling the length doubles the mechanical advantage.

Question 3

Which class of lever has the fulcrum between the effort and the load?

Accepted Answer

First class

Answer

A first-class lever has the fulcrum positioned between the effort force and the load, like a seesaw.

Question 4

A screw with a pitch of 0.5 cm is turned with a screwdriver handle of radius 2 cm. What is the mechanical advantage (use π ≈ 3.14)?

Accepted Answer

25.12

Answer

MA of a screw = 2π × radius / pitch = 2 × 3.14 × 2 / 0.5 = 25.12.

Question 5

In a fixed pulley system, what is the mechanical advantage?

Accepted Answer

1

Answer

A single fixed pulley has a mechanical advantage of 1 — it changes direction of force but does not multiply it.

OAR Test Practice Test

OAR Test Practice Test

OAR OAR Mechanical Comprehension: Simple Machines 2