Answer:
The correct option is (b).
Explanation:
Given that,
Electric field, 
We need to find the magnitude of the force on the electron as a result of the electric field.
We know that, the electric force is given by :

So, the required force on the electron is equal to
.
Answer:
The work done shall be 14715 Joules
Explanation:
The work done by a force 'F' in a displacement 'dy' is given by

At any position 'y' the weight shall be sum of weft of water and weight of string

Thus applying values we get

Answer:
v =2.02
Explanation:
v^2=0.05-4.9
v^2=-4.85
square root both side
v=2.02
^^^^this is a not a perfect square
Answer:
A telescope's angular resolution.
Explanation:
Diffraction limit is a minimum angular separation of two sources and it can be distinguished by the telescope. This angle is known as the diffraction limit. It is proportional to the wavelength of light and it has an inverse relation with the diameter of the telescope. Mathematically it is defined as
θ = 1.22λ/d
where θ is the angle, λ wavelength and d is the diameter of the objective mirror (lenz).