Question

1. a falling object:

a. falls at the same speed throughout the fall
b. constantly slows down throughout the fall
c. constantly speeds up throughout the fall until it reaches terminal velocity

Explanation:

When an object falls, initially the force of gravity (\(F_g = mg\)) acts on it. As it starts moving, air resistance (\(F_{air}\)) acts in the opposite direction. At the start, \(F_g>F_{air}\), so there is a net force (\(F_{net}=F_g - F_{air}\)) in the downward direction. According to Newton's second law (\(F = ma\)), this net force causes an acceleration (\(a=\frac{F_{net}}{m}\)) and the object speeds up. As the speed of the object increases, the air - resistance force also increases (\(F_{air}\propto v^2\) for turbulent flow). Eventually, \(F_{air}\) becomes equal to \(F_g\), so \(F_{net}=0\) and the object moves with a constant velocity called terminal velocity (\(v_t\)).

Answer:

C. constantly speeds up throughout the fall until it reaches terminal velocity