Question

Our galaxy, the Milky Way, has a diameter of about 100,000 light years. How many years would it take a spacecraft to cross the galaxy if it could travel at 99% the speed of light? A. 1.4 × 103 yrs B. 1.0 × 105 yrs C. 1.4 × 104 yrs D. 7.2 × 103 yrs E. None of these is correct.

Answer 1

The time is
`1*10^(5)\ yrs`

(B) is correct option.

Explanation :

Given that,

Diameter = 100000 light year

Velocity = 0.99 c

We need to calculate the time

Using formula of time

`t = (d)/(v)`

Put the value into the formula

`t =(100000 c)/(0.99c)`

`t =1*10^(5)\ yrs`

Hence, The time is
`1*10^(5)\ yrs`