Answer:
0 N
Explanation:
The elevator is under free fall. So, when a body is under free fall, the acceleration is only due to gravity. So, the acceleration of the elevator or the woman inside it, is acceleration due to gravity in the downward direction.
The spring scale gives the value of the normal force acting on the woman and doesn't give the exact weight of the woman. Under normal conditions, when the spring scale is at rest, then the upward normal force equals the weight and hence weight of a body is equal to the normal force acting on the body.
But, here, the body is not at rest. Weight\tex](mg)[/tex] acts in the downward direction and normal force
acts in the upward direction. The woman is moving down with acceleration equal to acceleration due to gravity
So, we apply Newton's second law on the woman.

Net force is equal to the difference of the downward force and upward force.

Now, 

Therefore, the reading on the spring scale is 0 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
Static friction
hope this helps
There are 3, Tubular, Clincher, and tubeless.