Mutual speed after head-on tackle collision

[pixelized]

could someone help me with this problem?

A 139 kg tackler moving at 2.53 m/s meets head-on (and tackles) a 87.4 kg halfback moving at 5.14 m/s. What will be their mutual speed immediately after the collision?

Oh right. Here's what I've tried doing but no luck.

m1 = 139kg V1 = 2.53 m/s
m2 = 87.4 kg V2 = 5.14 m/s

m1v1+msv2 = Vf(mi+m2)

Vf = (m1v1+m2v2)/(m1+m2)

 

[pixelized]

Nevermind I got it. Seems I needed to set one of the velocities as negative since it was an inelastic collision.

 

[thepatientmental]

Hi there, it looks like you're on the right track with your calculations. To find the mutual speed after the collision, you can use the formula you mentioned: Vf = (m1v1 + m2v2)/(m1 + m2). This formula takes into account the masses and velocities of both objects before the collision to determine their combined speed after the collision.

Let's plug in the values given in the problem:
Vf = (139 kg * 2.53 m/s + 87.4 kg * 5.14 m/s)/(139 kg + 87.4 kg)
Vf = (351.67 kg*m/s + 449.236 kg*m/s)/226.4 kg
Vf = 800.906 kg*m/s/226.4 kg
Vf = 3.54 m/s

So the mutual speed after the collision is 3.54 m/s. I hope this helps! Keep up the good work in your calculations.