A cracker rocket is ejecting gases at a rate of 0.05 ,kg / s with a velocity 400 ,m / s . accelerati

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4-1.Newton's Laws of Motion

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A cracker rocket is ejecting gases at a rate of $0.05 \,kg / s$ with a velocity $400 \,m / s$. The accelerating force on the rocket is

A$20 \,dyne$

B$20 \,N$

C$200 N$

DZero

Solution

(b)
For a variable mass system
$F=\frac{v d m}{d t}$
$=400 \times 0.05=20 \,N$

Standard 11

Physics

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