The outside observer, at rest relative to the spaceship, would see the spaceship
get shorter. and the clocks on the spaceship run slower than they should.
At the same time, the crew of the spaceship, looking back at the observer on
Earth, would see the observer on Earth get shorter, and the observer's clock
run slower than it should.
They would both be measuring what they see correctly.
Answer:
Answer: It takes 5,730 years for half the carbon-14 to change to nitrogen; this is the half-life of carbon-14. After another 5,730 years only one-quarter of the original carbon-14 will remain
Answer:

Explanation:
c = Speed of wave
= Density of medium
A = Area
= Frequency

Intensity of sound is given by

So,

We get

The ratio is 
Answer:
P = 3.5 D
Explanation:
As we know that convex lens is to be used to make the near point of eye to be correct
So we will have

here we have


now plug in all values into the formula


now for power of lens


so the power in dioptre is
P = 3.5 D