Question

Explain using the law of conservation of momemtum.    How does a balloon filled with air, upon being released, propel itself?

Answer 1

By coservation of momentum,

initial momentum of system(Pi) = final mimentum of system(Pf)

Let, initial mass of balloon = M

air released from balloon with velocity 'v' (Suppose in positive x-direction)

also mass released of air = m

velocity of balloon = V

given initial velocity = 0

So, Pi = 0

therefore, Pf is must equals to zero.

Pf = m*v + M*V = 0

V = -m*v/M

Since v is in +ve x-direction, So V will be in opposite direction, So a balloon filled with air , upon being released ,propel itself.

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