It takes 20s for a person A of mass 50kg to climb up the stairs ,while another person B of same mass does the same in 15s .compare work & power
Answers
work done of B=50×g×s
power=w d /time
=50gs/20=5/2gs
power of b =50gs/15=10/3gs
Answer: The work done of both persons are equal.
The power of a person B is more than the power of person A.
Explanation:
The expression for the work done is as follows;
W= mgs
Here, m is the mass, g is the acceleration due to gravity and s is the distance.
Calculate the work done for person A.
W= mgs
Put m= 50 kg.
W= 50gs
Calculate the work done for person B.
W= mgs
Put m= 50 kg.
W= 50gs
Therefore, the work done of both persons are equal.
The expression for the power is as follows;
[tex]P=\frac{W}{t}[\tex]
Calculate the power for person A.
[tex]P=\frac{W}{t}[\tex]
Put W= 50gs and t= 20s.
[tex]P=\frac{50gs}{20}[\tex]
[tex]P=2.5gs[\tex]
Calculate the power for person B.
[tex]P=\frac{W}{t}[\tex]
Put W= 50gs and t= 15 s.
[tex]P=\frac{50gs}{15}[\tex]
[tex]P=3.33gs[\tex]
Therefore, the power of a person B is more than the power of person A.