AS Daily A Level Physics question
In a school lab, a launcher fires a small rubber stopper at a fixed angle of 40° to the horizontal. Air resistance is negligible. If the launch speed is doubled while keeping the angle the same, what happens to the maximum height reached above the launch point?
Answer
The correct answer is C.
Correct: C — It increases by a factor of 4. A The height does not scale linearly with speed; it depends on the square of the vertical component, so doubling speed does more than just double the height. B A √2 factor would come from mixing up proportionalities; maximum height is not proportional to the square root of speed. C Height ∝ (vertical launch speed)^2, and doubling the launch speed doubles the vertical component, so the height becomes 2^2 = 4 times larger. D Angle alone does not fix the height; with the same angle, a higher launch speed gives a larger vertical component and thus a greater height.