Question

Two children stand on a platform at the top of a curving slide next to a backyard swimming pool. At the same moment the smaller child hops off to jump straight down into the pool, the bigger child releases herself at the top of the frictionless slide.
(i) Upon reaching the water, how does the kinetic energy of the smaller child compare with that of the larger child?

a.It is greater. b.It is less. c.The two energies are equal.

(ii) Upon reaching the water, how does the speed of the smaller child compare with that of the larger child is?

a.It is greater. b.It is less. c.The two speeds are equal.

(iii) During their motions from the platform to the water, how does the average acceleration of the smaller child compare with that of the larger child? a.It is greater. b.It is less. c.The two accelerations are equal.
d.The First and third are wrong

Answer 1

Answer:

Explanation:

i )

In a conservative field like gravitational field , loss of potential energy  or work done , depends upon the initial and final point and not the manner in which 2 nd point has been reached . Since the initial and final point is same in both the cases of straight and curved path , final velocity will remain same for both of them .

Hence , due to increased mass of larger child , his kinetic energy will be greater .

ii ) Since the initial and final point is same in both the cases of straight and curved path , final velocity will remain same for both of them .

iii ) Smaller child undergo free fall , therefore , he will fall with acceleration g . The larger child falls on curved path . So , he will have only a component of

vertical g at any moment  . hence average acceleration  will be less.