Power=work/time
power=50/20
50/20=2.5
Therefore A. 2.5 W
Answer:

Explanation:
According to Newton's first law:

The component of the force on the y-axis can be obtained through the Pythagorean Theorem. This is because the components are the cathetus of a right triangle and its hypotenuse is the magnitude of the force:

Replacing and solving for N:

Answer:
The final size is approximately equal to the initial size due to a very small relative increase of
in its size
Solution:
As per the question:
The energy of the proton beam, E = 250 GeV =
Distance covered by photon, d = 1 km = 1000 m
Mass of proton, 
The initial size of the wave packet, 
Now,
This is relativistic in nature
The rest mass energy associated with the proton is given by:


This energy of proton is 
Thus the speed of the proton, v
Now, the time taken to cover 1 km = 1000 m of the distance:
T = 
T = 
Now, in accordance to the dispersion factor;


Thus the increase in wave packet's width is relatively quite small.
Hence, we can say that:

where
= final width
Answer:
Part a)
f = 1911.5 Hz
Part b)

Explanation:
Here the source and observer both are moving towards each other
so we know that the apparent frequency is given as

here we know that



now we will have


Part b)
Apparent wavelength is given by the formula

here we will have

