Answer:
A. Increasing the diameter of the steering wheel
Explanation:
The steering wheel is an example of wheel-and-axle machine, where:
- the wheel is the sterring wheel
- the axle is the shaft
The mechanical advantage of a wheel and axle system is given by
[tex]MA = \frac{r_w}{r_a}[/tex]
where [tex]r_w[/tex] is the radius of the wheel and [tex]r_a[/tex] is the radius of the axle.
Let's now analyze each option:
A. Increasing the diameter of the steering wheel --> this will increase [tex]r_w[/tex], so this will increase the mechanical advantage --> correct
B. Decreasing the diameter of the steering wheel --> this will decrease [tex]r_w[/tex], so this will decrease the mechanical advantage --> wrong
C. Decreasing the length of the shaft --> this will not affect [tex]r_a[/tex], so this won't affect the mechanical advantage --> wrong
D. Increasing the length of the shaft --> this will not affect [tex]r_a[/tex], so this won't affect the mechanical advantage --> wrong
So, correct choice is A.
