when skydiving, its not just freely falling under Earth's gravity. Additional force called drag acts against the gravity which slows down the rate of fall. Drag is caused by the air molecules which push against the body as it falls through them. This is actually a significant amount of force which slows down the rate of fall of the body. Drag depends on the contact surface area and weight. More the surface area in contact, more would be the drag. The sitting position of the skydiver would experience less drag than the chest down position because of the less contact surface area of the body with the air molecules while in the former case. No two persons have identical body shape and weight. Hence, the rate of fall can be made nearly equal but not exactly equal. This is would be possible when they are having same body position.
Answer:
Option A is correct.
The wires will be arranged in order of increasing resistance.
Explanation:
The resistance of a wire is given by
r = (ρl)/A
where r = resistance of the wire
ρ = resistivity of the wire
L = length of the wire
A = cross sectional area of the wire
Provided all the other parameters are constant, resistance is inversely proportional to cross sectional area
r ∝ (1/A)
And the the cross sectional Area of the wire increases with increase in thickness & decreases with thickness
So, decreasing thickness ----> Decreasing Cross sectional Area ----> Increasing resistance.
