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Sir/Madam can you please tell me the answer of question no. - 14 , 15

Q14. A space craft flying in a straight course with a velocity of 75 km s^{–1} fires its rocket motors for 6.0 s. At the end of this time, its speed is 120 Km s^{–1} in the same direction. Find : (i) the space craft's average acceleration while the motors were firing, (ii) the distance travelled by the space craft in the first 10 s after the rocket motors were started, the motors having been in action for only 6.0 s.

**Ans. (i) 7.5 Km s**^{–2}, (ii) 1065 Km

Q15. A train starts from rest and accelerates uniformly at a rate of 2 m s^{–2} for 10 s. It then maintains a constant speed for 200 s. The brakes are then applied and the train is uniformly retarded and comes to rest in 50 s. Find : (i) the maximum velocity reached, (ii) the retardation in the last 50 s, (iii) the total distance travelled, and (iv) the average velocity of the train.

** Ans. (i) 20 m s**^{–1}, (ii) 0-4 m s^{–2}, (iii) 4600 m, (iv) 17.69 m s^{–1}

^{–2}, (ii) 1065 Km

^{–1}, (ii) 0-4 m s

^{–2}, (iii) 4600 m, (iv) 17.69 m s

^{–1}

Here is a link given below for the question number 14 which will help you to solve this question with proper explanation .

https://www.meritnation.com/ask-answer/question/a-space-craft-is-flying-in-a-straight-course-with-the-veloc/physics/2545194

Kindly ask different question in different posts .

Regards

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