If the mass of the products measured 120 g, what would be the mass of the reactants?

a: 30 g
b: 60 g
c: 120 g
d: 240 g

What is relative velocity? in which condition is relative velocity known by adding the velocity of the first body and that of the second body

Two masses are connected by a rope that hangs over a pulley as shown below. the pulley is a uniform cylinder of radius 푅=0.381meters and mass 푀=3.1푘푔. initially 푚"is on the ground and 푚#rests 2.5 meters above the ground. if the system is released, use conservation of energy to determine the speed of 푚#just before it strikes the ground. assume the pulley bearing is frictionless.

If anyonee has done the momentum lab practical in physics can you give me the answers i am s lostt rnn : (