Suppose the two speeds of a two canoes after they are pushed apart are 0.60 m/s for canoe 1 and 0.45 m/s for canoe 2. if the mass of canoe 1 is 350kg, what is the mass of canoe 2?

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# 1 Answer

Assuming that the canoes were at rest when they were pushed apart, the total momentum in the system must be zero. This means that the momentum of canoe 1 must have the same magnitude as the momentum of canoe 2, but in opposite directions.

p_{1} = -p_{2}

m_{1}v_{1} = -m_{2}v_{2}

m_{1}v_{1}/(-v_{2}) = m_{2}

m_{2} = 350kg(0.60m/s)/[-(-0.45m/s)]

m_{x} = 470 kg (Rounded to 2 significant figures)