Question

1. Two football players with mass 90 kg and 105 kg run directly toward each other withspeeds 5 m/s and 3 m/s respectively, if they grab each other as they collide, what is thecombined speed of the players just after the collision?

Answer 1

Given:

The mass of the first football player is m1 = 90 kg

The mass of the second football player is m2 = 105 kg

The initial speed of first football player is v_1i = 5 m/s

The initial speed of second football player is v_2i = 3 m/s

To find the speed of the combined mass after the collision.

Step-by-step explanation:

According to the conservation of momentum,

`\begin{gathered} m1v_(1i)+m2v_(2i)=(m1+m2)v_f \\ v_f=(m1v_(1i)+m2v_(2i))/((m1+m2)) \end{gathered}`

On substituting the values, the speed of the combined mass after the collision will be

`\begin{gathered} v_f=((90*5)+(105*3))/(90+105) \\ =3.92\text{ m/s} \end{gathered}`

Final Answer: The speed of the combined mass after the collision is 3.92 m/s