Which of the following would increase the mechanical advantage of a steering wheel?
a. increasing the diameter of the steering wheel
b. decreasing the diameter of the steering wheel
c. decreasing the length of the shaft
d. increasing the length of the shaft

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

where is the radius of the wheel and is the radius of the axle.

Let's now analyze each option:

A. Increasing the diameter of the steering wheel  --> this will increase , so this will increase the mechanical advantage --> correct

B. Decreasing the diameter of the steering wheel  -->  this will decrease , so this will decrease the mechanical advantage --> wrong

C. Decreasing the length of the shaft  --> this will not affect , so this won't affect the mechanical advantage --> wrong

D. Increasing the length of the shaft  --> this will not affect , so this won't affect the mechanical advantage --> wrong

So, correct choice is A.

it would be kevlar ^^

it is given that trillions of microbes make up to 1% to 3% of the body mass.

let's take average of this percentage: 2%

consider the average mass of the human body as 70 kg.

then, trillions of microbes would have mass  

therefore, 100 trillion micro-organisms would weigh:

this is an approximate value and could change depending on the mass of the human body and percentage of the microbes present in it.

average mass per microorganism =