A single electron has a charge of

Therefore, if we have an excess of

electrons, the total net charge will be the product between the charge of a single electron and the total number of electrons in excess:
Answer:
Resistance in the flash tube, 
Explanation:
It is given that,
Speed of the bullet, v = 500 m/s
Distance between one RC constant, d = 1 mm = 0.001 m
Capacitance, 
The time constant of RC circuit is given by :

R is the resistance in the flash tube
..........(1)
Speed of the bullet is given by total distance divided by total time taken as :




Equation (1) becomes :


So, the resistance in the flash tube is
. Hence, this is the required solution.
The colour of the star and the brightness.