Question

Two identical twins with the same mass take the stairs to the second floor of a house. Twin A gets there in 30s; Twin B gets there in 15s. Which twin did more work against gravity? Which twin used more power?

A) Twin A for both
B) Twin B for both
C) Twin A did more work, Twin B used more power
D) Twin B did more work, Twin A used more power

Answer 1

Both twins did the same amount of work against gravity by climbing the same distance, but Twin B used more power because Twin B climbed the stairs in less time (C).

Step-by-step explanation:

When considering the work done against gravity by two individuals with the same mass climbing to the same height, the amount of work done is equal for both. This is because work is defined as the force exerted over a distance (W=fd), and since they're lifting their identical masses to the same height, the force due to gravity and distance are the same for both twins.

Power, however, is defined as the rate at which work is done (Power = Work/time). Therefore, the twin who takes less time to climb the stairs has used more power. In this case, Twin A took 30 seconds and Twin B took 15 seconds to reach the second floor. While both twins have done the same amount of work against gravity, Twin B has used more power to reach the second floor because the work was done in a shorter amount of time. Thus, the correct answer is Twin B used more power but both did the same amount of work.