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Fuel is consumed at the rate of 50 kg s^(-1)in a rocket. Find the thrust on the rocket if the velocity of the exhaust gases is 2 km s^(-1). Also calculate the velocity of the rocket at the instant, when its mass is reduced to l/10th of its initial mass if its initial velocity is zero, (neglect gravity) |
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Answer» Solution :`(dm)/(dt) = 50 kgs^(-1) , U=2 KM s^(-1) = 2 xx 10^(3) ms^(-1)` Initial velocity, `u_(0)=0` (i) The thrust on the ROCKET. `F =u(dm)/(dt) = 2 xx 10^(3) xx 50 = 1 xx 10^(5)` N (ii) The velocity of the rocket. `v=v_(0) + ulog_(e) m_(0)/m` `=0+2 xx 10^(3) log_(e) [m_(0)/m_(0) xx 10] [THEREFORE m=m_(0)/10]` `=4.606 xx 10^(3) m//s` |
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