Answer:
force becomes one - ninth
Explanation:
According to Coulomb's law in electrostatics, two charges can exert a force of attraction or repulsion on each other which is directly proportional to the product of two charges and inversely proportional to the square of distance between them.
Here both the charges remains same but the distance is variable.
So, we can say that
.... (1)
Where d be the distance between the tow charges
As the distance between two charges increases by factor of three, let the new force be F'.
.... (2)
Divide equation (2) by equation (1), we get


Thus, the force becomes one - ninth times the initial force.
Answer:

Explanation:
As per mechanical energy conservation we can say that here since friction is present in the barrel so we will have
Work done by friction force = Loss in mechanical energy
so we will have

here we know that



Initial compression in the spring is given as



now from above equation




Answer:
The focal length of the lens is 34.047 cm
The power of the needed corrective lens is 2.937 diopter.
Explanation:
Distance of the object from the lens,u = 26 cm
Distance of the image from the lens ,v= -110 cm
(Image is forming on the other side of the lens)
Since ,lens of the human eye is converging lens,convex lens.
Using a lens formula:


f = 34.047 cm = 0.3404 m
Power of the lens = P
