Answer:
The speed of the galaxy relative to the Earth is
.
Explanation:
We have,
(a) Wavelength emitted by light at distant galaxy is 434.1 nm. On earth, the wavelength of this light is measured to be 438.6 nm. It can be seen that the wavelength of light reduces as it reaches Earth. It is called Red shift. As per Doppler's effect, we can say that the galaxy is receding from the Earth.
(b) Let v is the speed of the galaxy relative to the Earth. It can be given by :

So, the speed of the galaxy relative to the Earth is
.
The question is incomplete. If D=1/T then the answer is D, but if instead of =, there is a proportional sign, then the answer is C.
It is the same if a white father and a white mother give birth to a black kid, so the mother accuses the father for having (let's say mating) with a black women.
F=dP/dt. So you want the momentum to change as slowly as possible in time to minimize the force. So as you catch the egg, let your hand move backward with it for awhile, slowly bringing it to a stop. If you hold your hand steady when you catch it the force due to the impact could break it.
Answer:
The conditions necessary for hearing the echo. The distance between the sound source and the reflecting surface must not be less than 17 metres where the time period between hearing the original sound and its echo should not be less than 0.1 of a second.