1. Were the collisions elastic or inelastic? EXPLAIN. Inelastic, Because the kinetic energy will be changed to some other form of energy in the collision. 2. Was momentum conserved during the collisions? EXPLAIN. 3. Was mechanical energy (E= K+U) conserved during the collisions? EXPLAIN. 4. Was the momentum of the pendulum and the ball conserved after collision? EXPLAIN.

when jerome paddle in flowing river towards east the net speed of jerome will increase

so the net speed of jerome will be given as

now the speed of paul will be same as it is given as he is running on the ground

so

so here we can say since the speed of jerome is more so he will win the race

now as we know the distance so the time difference is given as

so jerome will reach first and the time difference will be 203.55 s or 3.4 min

the doppler effect is used by weather forecasters to measure 

moving clouds