Question

two boys Aand B weighing 60 kg and 40 kg respectively climb on a staircase each carrying a load of 20 kg on the head .the staircase has 10 steps each of height 50 cm.if A takes 20 seconds to climb and b takes 10 s to climb then
a)who possess greater power
b) what is the ratio of their powers​

Answer 1

Answer:

dhruv apke question ka ye ans bilkul correct h

jo dkashyap ne diya h

Answer 2

Answer:

Among the two boys B possess greater power and ratio of their power is 2:3.

Explanation:

For A

Mass= 60 kg

Load=20 kg

Total height=10×50cm=500cm=5m

Total work done by the boy in covering 10 steps is,

$W=Mgh$ (1)

where,

W=work done

M=total mass of the boy and the load=60kg+20kg=80kg

By putting the required values in equation (1) we get;

$W_A=80\times 10\times 5=4000J$       (2)

Now we have to calculate power,

$P=\frac{W}{t}$          (3)

Where,

P=power

W=work done

t=time

By substituting the required values in equation (2) we get;

$P_A=\frac{4000}{20}=200watt$     (4)

For B

Mass=40 kg

Load=20 kg

Total height=5m

Total work done by the boy in covering 10 steps is,

$W_B=60\times 10 \times 5=3000J$     (5)

Now we have to calculate power,

$P_B=\frac{3000}{10}=300watts$      (6)

Now as per the question,

(a) From the equations (4) and (6) we can see that B has greater power.

(b) The ratio of power is,

$\frac{P_A}{P_B}=\frac{200}{300}=\frac{2}{3}$

Hence, among the two boys B possess greater power and ratio of their power is 2:3.