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n a rocket, the mass of the fuel is 90% of the total mass. The rocket is blasted from the launching pad. If the exhaust gases are ejected at a speed of 1000 S^(-1) what is the maximum speed attained by the rocket? (Neglect the effects of gravity and air resistance). |
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Answer» `2.3 km//s` Since fuel is 90% of total mass :.mass of container, `m_(c) = m_(0) -(90)/(100)m_(0)` `m_(c)=(1)/(10)m_(0)` `:.(m_(0))/(m_(c))=10` Now burnt out speed `upsilon_(B)=ulog_(e)(m_(0))/(m_(c))=2.303u log_(10)10` `=2.303xx1000xx1=2303m//s=2.3 kms^(-1)` Hence correct choice is (a) |
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