Answer:
(A) V = 9.89m/s
(B) U = -2.50m/s
(C) ΔK.E = –377047J
(D) ΔK.E = –257750J
Explanation:
The full solution can be found in the attachment below. The east has been chosen as the direction for positivity.
This problem involves the principle of momentum conservation. This principle states that the total momentum before collision is equal to the total momentum after collision. This problem is an inelastic kind of collision for which the momentum is conserved but the kinetic energy is not. The kinetic energy after collision is always lesser than that before collision. The balance is converted into heat by friction, and also sound energy.
See attachment below for full solution.
Power of the glasses required is given as +2.5 D
this shows that person is having Farsightedness in which he can objects placed far clearly but he is not able to see clearly to the near objects
For normal vision near point of eye is 25 cm
Let say person can see the objects clearly at distance "d" from the eye
now from the formula
here given that
also we know that
from above equation now
So the distance of object must be 66.6 cm
Answer:
f = 1 Hz
Explanation:
From the attached figure, we find that the time period of the wave is 1 second.
It is a longitudinal wave. It travel in the form of compression and rarefaction. The relation between time period T and frequency f is given by :
Hence, the frequency of this wave is 1 Hz.