4.Jessica Diggins a US world champion cross country skier is participating in the

Explanation:

Given that,

Initial speed, u = 5.1 m/s

Final speed, v = 6.2 m/s

Time, t = 25 s

We need to find acceleration. We know that,

acceleration = rate of change of velocity

So, her acceleration is .

Linear momentum = 42.3 kg·m/s

Kinetic Energy = 38.07 J

Explanation:

We should know that before the collision occured, the momentum and KE of the disk are zero

Thus, the system momentum is given as;

p = mv

p = 23.5kg x 1.80m/s = 42.3 kg·m/s

Now for the system Kinetic Energy. It's given as;

KE = ½ mv²

KE = ½ x 23.5 kg x (1.80m/s)² = 38.07 J

After the collision, we'll discover that the momentum remains the same (mass increases but velocity decreases) and that some Kinetic energy(KE) has been lost.