Question

Who will answer this numerical physics will be marked as brainliest

Answer 1

Question 10:

Since, the masses are identical.

Velocity of one car(v) = 15 km/h

Velocity of second car (u) = 20 km/h

Kinetic energy ratio = $\frac{2mv^2}{2mu^2}$

Kinetic energy ratio = $\frac{15^2}{30^2}$

Kinetic energy ratio = 1 : 4

Question 11:

Energy spent = $4 \times 10^5$

Time taken = 10 sec

$Power = \frac{Energy}{time}$

$Power = \frac{4\times 10^5}{10}$

$Power = 4 \times 10^4$ Watts

Question 12:

Mass of both the girls is same = m

acceleration due to gravity = g

Height is also same = H

Work done is both the cases = mgH

Hence, the ratio of the work done is 1 : 1

Power = $\frac{Work}{time}$

Since, the work done is same in both the cases. Hence, both will cancel out.

$\frac{(Power)_A}{(Power)_B} = \frac{15}{20}$

Hence, the ratio is 3 : 4