Question

1. th a physics class, two students volunteer to participate in an experiment about the rate

of energy transfer (power). They find a set of stairs on campus and want to use them to
determine how much power they are able to produce. They conduct their investigation
and collect the following data. Which student produced more watts of power in their stair
climb and why? (AKS 5C, DOK 2)
Student Mass
Height of 1
stair
# of
stairs
Time to climb
stairs
Student
500
0.15m
20
15 s
Student
700
Ν
0.15m
20
21 s
a. Student 1 produced more watts of power because she was able to reach the top
of the stairs more quickly than Student 2
b. Student 2 produced more watts of power because he had to lift a greater mass up
the stairs than Student 1 so he had to do more work
c. Both students produced equal watts of power. Since power is defined as
work/time, Student l's lighter mass but faster time to reach the same height equals
Cidont' havier mass and slower to time to reach the same height.

Answer 1

Option c

Step-by-step explanation:

In this experiment we get to know that the power depends on both work done and amount of time taken

Here as height of 1 stair and number of stairs are same, the displacement in calculation of work will be the same and therefore work depends on the force

For climbing internally we require a force equal to the (mass of the body) × (acceleration due to gravity) and therefore the force we apply will be dependent on the mass of the body as acceleration due to gravity will be same for both

Work done in case of student 1 will be (500 × g) = (500 × g) × 20 ×0·15

Work done in case of student 2 will be (700 × g) = (700 × g) × 20 ×0·15

Power is defined as work done per unit time

∴ Power = (Work done) ÷ (time taken)

Power required in case of student 1 will be ((500 × g) × 20 ×0·15) ÷ 15 = ((100 × g) × 20 ×0·15) ÷ 3

Power required in case of student 2 will be ((700 × g) × 20 ×0·15) ÷ 21 = ((100 × g) × 20 ×0·15) ÷ 3

From above we can say that the power required in case of both the students are same