Question

5. When passing a turn, the driver exerts on the steering wheel a pair of forces with torque M = + 120 Nm. a) Calculate the force exerted by the driver on the steering wheel, when it is known that the radius of the steering wheel is 20cm. b) Make a simple figure and show the direction of the moment, whether it is clockwise or counterclockwise. c) What kind of turn did the driver take, right or left?

Answer 1

a) By definition, the torque is:

$$M = Fl$$

where $F$ is the force exerted by the driver on the steering wheel, and $l = 20cm = 0.2m$ is the radius of the wheel. Substituting $M = 60N\cdot m$ (since we want to calculate only one from the pair of identical forces), obtain:

$$F = \dfrac{M}{l}\\ F = \dfrac{60N\cdot m}{0.2m} = 300N$$

b)

If we direct the positive x-axis toward the driver, then looking from his or her perspective, the rotation will be counterclockwise.

c) It is the left turn.