Two lumps of clay having equal masses and speeds, but traveling in opposite directions, collide and stick together. which of the following statements about this system of lumps must be true? a) the momentum of the system is conserved during the collision. b) the kinetic energy of the system is conserved during the collision. c) the two masses lose all their kinetic energy during the collision. d) the velocity of the center of mass of the system is the same after the collision as it was before the collision.

Apulley with mass mp and a radius rp is attached to the ceiling, in a gravity field of 9.81 m/s2 and rotates with no friction about its pivot.

Is there a point between a 10 nc charge and a 20 nc charge at which the electric field is zero?

Aballoon is rising vertically upwards at a velocity of 10m/s. when it is at a height of 45m from the ground, a parachute bails out from it. after 3s he opens his parachute and decelerates ata a constant rate 5m/s.when. (a) what was the height of the parachutist above the ground when he opened his parachute? (b)how far is the parachutist from the balloon at t=3s? (c)with what velocity does the parachutist hit the ground? (d)after how long does the parachutist hit the ground after his exist from the balloon?