Answer:
Part a)

Part b)

Explanation:
Part a)
Electric flux entering into the base
so it is given as





Part b)
Now since we know that there is no enclosed charge in the hemisphere
so net flux must be zero



Answer:
Velocity=1.1m/s
Amplitude=0.35m
Explanation:
Given:
time 't' = 2.9s
wavelength 'λ'= 5.5m
distance 'd'=0.7m
The time period 't' is the time b/w two successive waves. Therefore, the time it takes from the boat to travel from its highest point to its lowest is a half period.
So, T = 2 x 2.9 => 5.8 s
As we know that frequency is the reciprocal of time period, we have
f= 1/T = 1/5.8 =>0.2 Hz
In order to find how fast are the waves traveling, the velocity is given by
Velocity = f λ
V= 0.2 x 5.5 =>1.1m/s
The distance between the boat's highest point to its lowest point is double the amplitude.
Therefore , we can write
Amplitude 'A'= d/2 =>0.7/2 =>0.35m
Answer:

Explanation:
At thermal equilibrium we have heat given by aluminium must be equal to the heat absorbed by the water
so we will have


so we will have

so we have

so we have


The galaxies aren't distributed randomly throughout the universe but they are grouped in gravitationally bound clusters.