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The first & second state of two stage rocket separately weight 100 kg and 10 kg and contain 800 kg and 90 kg fuel respectively. If the exhaust velocity of gases is 2 km/sec then find velocity of rocket (nearly (log_(10)5=0.6990) (neglet gravity). |
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Answer» Solution :`V=V_(0)+2.3` ulog `(m_(0)//m)` VELOCITY as the FIRST stage is detached `= V_(0)` `V_(0)=2.3` ulog `(m_(0)//m)` `=2.3xx2xx10^(3)XX LOG(1000//200)` `=2.3xx2xx0.699xx10^(3)=3.2xx10^(3)` Velocity acquired with second stage = V `V=V_(0)+2.3u log(m_(0)//m)` `=3.2xx10^(3)+2.3xx2xx10^(3)xx log(100//10)` `=3.2xx10^(3)+4.6xx10^(3)=7.8xx10^(3)m//s` |
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