Question

Buffy is rolling along in her 10.4 kg wagon at 3.4 m/s (in the positive direction) when she jumps off the back. She continues to move forward at 1.7 m/s relative to the ground. This causes her wagon to go speeding forward at 8.04 m/s relative to the ground. How much does Buffy weigh

Answer 1

Buffy weigh's 28.39 kg

Step-by-step explanation:

Given;

mass of Buffy and wagon, M = 10.4 kg

final velocity of Buffy - wagon system, v = 3.4 m/s

Buffy's velocity relative to the ground, u₁ = 1.7 m/s

Wagon's velocity relative to the ground, u₂ = 8.04 m/s

Buffy's velocity = 1.7 - 3.4 = - 1.7 m/s

Wagon's velocity = 8.04 - 3.4 = 4.64 m/s

Apply the principle of conservation of linear momentum;

1.7 x m = 4.64 x 10.4

where;

m is mass of wagon

1.7 m = 48.256

m = 48.256 / 1.7

m = 28.39 kg

Therefore, Buffy weigh's 28.39 kg