Kinetic energy is energy of motion. Pick choice-A, at the top of the swing, where she stops moving & then goes the other way.
Answer:


Given:
Initial velocity (u) = 0 m/s
Final velocity (v) = 20 m/s
Time taken (t) = 10 sec
To Find:
(i) Acceleration (a)
(ii) Distance covered (s)
Explanation:












The change in distance is 30 because if you subtract both number you'll get 30
Explanation:
It is given that,
Mass of the box, m = 100 kg
Left rope makes an angle of 20 degrees with the vertical, and the right rope makes an angle of 40 degrees.
From the attached figure, the x and y component of forces is given by :






Let
and
is the resultant in x and y direction.


As the system is balanced the net force acting on it is 0. So,
.............(1)
..................(2)
On solving equation (1) and (2) we get:
(tension on the left rope)
(tension on the right rope)
So, the tension on the right rope is 1063.36 N. Hence, this is the required solution.