Question

2. The distance of a Galaxy from the Earth is 8.2 × 10 27 m assuming the speed of light to be 3 ×10 8 m/s. Find the time taken by light to travel this distance.

3. The mass of a nitrogen atom is 14 u, find its mass in kilogram.

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Answer 1

Explanation:

Given:

distance = 5.6×10

25

m

speed = 3×10

8

ms

−1

Time = ?

Time taken =

speed

distancetravelled

=

3×10

8

5.6×10

25

=1.867×10

17

s