1. Ideal Mechanical Advantage (IMA): 9
Explanation:
For a wheel and axle system like the steering wheel, the IMA is given by:
where
is the radius of the wheel
is the radius of the axle
For the steering wheel of the problem, we see that 
and 
, so the IMA is
2. Efficiency: 88.9%
Explanation:
The efficiency of a system is defined as the ratio between the AMA (actual mechanical advantage) and the IMA:
In this problem, AMA=8 and IMA=9, so the efficiency is
Answer:
D. The tea loses heat to the spoon causing the spoon to become warmer
Explanation:
When the silver spoon at a lower temperature than the tea, is added to the tea, it makes thermal contact. Hence, the heat transfer starts between the two until the equilibrium is reached. We know that the heat transfer takes place from the body with a higher temperature to a body with a lower temperature. As a result, the body with higher temperature loses heat and its temperature lowers down. While the body with a lower temperature gains heat and its temperature rises.
Therefore, the correct option is:
<u>D. The tea loses heat to the spoon causing the spoon to become warmer</u>
