OAR OAR Mechanical Comprehension: Forces 4

Question 1

A lever has its fulcrum at the center. A 40 N force is applied 2 m from the fulcrum. To balance, what force must be applied 4 m from the fulcrum on the other side?

Accepted Answer

20 N

Answer

80 N

Answer

40 N

Answer

10 N

Question 2

Which quantity represents the rotational effect of a force about a pivot point?

Accepted Answer

Torque

Answer

Momentum

Answer

Impulse

Answer

Power

Question 3

An object moves in a circle at constant speed. The net force on the object is directed:

Accepted Answer

Inward toward the center

Answer

Tangent to the circle

Answer

Outward from the center

Answer

Opposite to velocity

Question 4

Two workers push a crate in the same direction: one with 250 N and one with 180 N. A friction force of 130 N opposes motion. What is the net force?

Accepted Answer

300 N

Answer

560 N

Answer

430 N

Answer

60 N

Question 5

If you double the mass of an object while keeping the net force constant, what happens to its acceleration?

Accepted Answer

Halves

Answer

Doubles

Answer

Stays the same

Answer

Quadruples

Question 6

A spring scale reads 80 N when a block hangs at rest. The block is then placed on a frictionless table and pulled horizontally with 80 N. What is the normal force from the table?

Accepted Answer

80 N

Answer

0 N

Answer

160 N

Answer

113 N

Question 7

A 1,000 N crate is dragged up a frictionless ramp inclined at 30°. What force parallel to the ramp is needed to move it at constant speed?

Accepted Answer

500 N

Answer

866 N

Answer

1,000 N

Answer

1,154 N