Question
What is not a requirement for two forces to act as a couple?
(A) The two forces act in opposite directions.
(B) The two forces act through the same point.
(C) The two forces combine to produce zero resultant force.
(D) The two forces have equal magnitude.
Answer/Explanation
Ans: B
Question
A rod is pivoted at point O.
A force F is applied to the rod at point W, as shown.
What is the moment of the force F about O?
A F$\times$ distance OX
B F $\times$ distance OY
C F $\times$ distance WO
D F $\times$ distance WX
▶️Answer/Explanation
Ans: B
Question
A farmer is trying to lift the corner of a large water tank. She uses a metal rod as a lever.
The vertical force from the farmer is constant and is always applied to the end of the rod.
Which change must increase the upward force on the water tank?
(A) using a longer rod and moving the pivot closer to the tank
(B) using a longer rod and moving the pivot further away from the tank
(C) using a shorter rod and moving the pivot closer to the tank
(D) using a shorter rod and moving the pivot further away from the tank
▶️Answer/Explanation
Ans: C
Question
The driver of a car applies two parallel forces to a steering wheel, as shown.
Each force has a magnitude of 15 N and acts in the direction shown. The steering wheel has a diameter of 0.40 m.
What is the torque exerted on the steering wheel?
(A) 1.3 N m
(B) 2.5 N m
(C) 2.7 N m
(D) 5.4 N m
▶️Answer/Explanation
Ans: D