Answer:
The mass of the receiver is 68.862 kg
Step-by-step explanation:
Given;
let mass of the receiver be "m₁"
initial velocity of the receiver, u₁ = 0
mass of the tackler, m₂ = 156 kg
initial velocity of the tackler, u₂ = 6.89 m/s
their final velocity, v = 4.78 m/s
Apply the principle of conservation of linear momentum, for inelastic collision;
m₁u₁ + m₂u₂ = v(m₁ + m₂)
(m₁ x 0) + (156 x 6.89) = 4.78(m₁ + 156)
0 + 1074.84 = 4.78 (m₁ + 156)
1074.84 = 4.78 (m₁ + 156)
m₁ + 156 = 1074.84 / 4.78
m₁ + 156 = 224.862
m₁ = 224.862 - 156
m₁ = 68.862 kg
Therefore, the mass of the receiver is 68.862 kg