Physics-
General
Easy
Question
When the mass of a system is variable, a thrust force has to be applied on it in addition to all other forces acting on it. This thrust force is given by 
Here 
is the relative velocity with which the mass dm either enters or leaves the system. A car has total mass 50 kg. Gases are ejected from this backwards with relative velocity 20 m/s. The rate of ejection of gas is 2 kg/total mass of gas is 20 kg. Coefficient of friction between the car and road is 
= 0.1 Maximum speed of car will be v = ..... m/s 
- 0.6
- 0.8
- 1.0
- 1.2
The correct answer is: 0.6
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