# physics

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An interstellar ship has a mass of 1.20 X10^6 kg and is initially at rest relative to a star system. a) what constant acceleration is needed to ring the ship up to a speed of .10c (where c is the speed of light, 3.0X10^8 m/s) relative to the star system in 3 days? b) what is that acceleration in g units? c) what force is required for the accelaration? d) If the engines are shut down when .10c is reached (the speed then remains consant) how long does the ship take (start to finish) to journey 5 light months the distance that light travels in 5 months?

I found this question to be quite difficult will you please clearify each part of the question for me? I couldn't figure out what to do.

For (a), compute the velocity change needed in m/s and divide it by three says (converted to seconds). That will be the required acceleration im m/s^2
(b) To convert the acceleration to g's divide by 9.8 m^2/s per g
(c) F = m a
(d) at a speed of 0.1 c, it takes the spacecraft 10 times as long is it would take light to travel the same distance.

• physics - ,

Hello, I know this is 3 years late but for people like me who just needed your hints, this basically means that for (a)
take .10(3x10^8)(m/s) and divide it by 3 days/24hrs/3600s and you will get your m/s^2
For (b), take what you got in (a) and divide it by 9.8m/s^2 to get the magnitude.
(c), Multiply (a) by the mass of the ship.
(d) the hint basically answered it..