Answer: 
It is given that:
Density of material =ρ
radius of inner spherical shell = 
radius of outer spherical shell=
we know that the volume of sphere is 
Volume of the given spherical shell = 
Then mass of the spherical shell can be calculate as:
Mass, m=density/ volume
Answer:
GIVEN
u is 40m/s and v=60m/s
time is 4s
therefore acceleration =60-40/4
=20/4=5m/s^2
b)next 2 sec=70m/s
The answer is 2,1,3,2
1. increased production 2. rising demand (occurs twice) 3. increased hiring
hope this helps :)
Answer:
No. If you take 5$ from your wallet and place on the shelf, does it change its value - No. So if you take the water from class(does not matter how much) and pour all of it somewhere else, it doesn't change its mass, yet it changes its shape.
The energy of a single photon is given by
where
is the Planck constant
f is the frequency of the wave (of the photon)
In our problem, the radio wave has a frequency of
, so if we put this value into the previous formula, we can find the energy of a single photon of this electromagnetic wave:
