Answer:
(a) Explained below
(b)
(c) Yes
Explanation:
<u>Law Of Conservation Of Linear Momentum</u>
The total linear momentum of a system of particles or objects is conserved unless an external force is acting on the system. The formula for the momentum of a body with mass m and velocity v is P=mv. If there is a system of bodies, then the total linear momentum is the sum of the individual momentums
When objects collide and join together, the only final mass is the sum of all masses, all traveling at the same speed.
Our fullback runs at
. Two two 68-kg linebackers attempt to stop him, one at -2.0 m/s and the other at -4.0 m/s. The negative value is because the run against the positive direction, taken in the direction of the fullback.
(a) Before the event, there is a total linear momentum, computed as the sum of the momentums of each player as shown
After the collision, all the players keep joined in one single mass of.
They will move at a speed which will be computed below
(b) The final momentum of the system is
Since the linear momentum is conserved, the final speed is common to all of the players. Let's solve to find it
(c) Since the final speed of the players is positive, it means the touchdown was actually scored, the fullback moved forward across the goal line, the positive reference.