Question

A rocket is fired vertically from the ground. It moves upwards with a constant acceleration of 10m/s^2 for 30 seconds, after which the fuel is consumed. After what time from the instant of firing, the rocket will attain the maximum height? (Take g=10m/s^2)

Answer 1

calculate the velocity of the rocket after 30 seconds.. !.. and then use your 1d kinematics to solve the problem..

Answer 2

@Mashy here will the intitial velocity be taken 0??..

Answer 3

here the options are given as 75s , 60s , 45s and 30s...so what should be the answer according to u?

Answer 4

yes.. you have to take the initial velocity as zero.. and then compute the velocity after 30 seconds.. using 10m/s^2 uniform acceleration.... then do another computation by taking that newly computed velocity as the initial velocity and find time for max height.. !!

Answer 5

ohhhh...ok...let me first try that out...

Answer 6

yea.. sure :).. if you don't get the answer.. show me your work here! .. ll tell whats wrong

Answer 7

in the another calculation...i should take the acceleration as that g=10m/s^2...and in that one i should take the final velocity as 0 ..?,,,right?..

Answer 8

if in the second case i tak final velocity 0 ...then i get answer as 30 s ..easily..?.