Two rocks with masses 050 kg and 25 kg are dropped from a 12

Two rocks, with masses 0.50 kg and 2.5 kg, are dropped from a 12 m high tower. Find the momentum vector or each rock as it strikes the ground. If a ball with a mass of 0.120 kg is thrown horizontally, what is the ball\'s change in momentum due to gravity in 1.5 seconds? Consider a 75 cm pendulum with a 0.150 kg bob. The pendulum is pulled to the horizontal position and released from rest. What is the bob\'s momentum when the pendulum makes an angle of pi/4 with the vertical? What is the bob\'s momentum when the pendulum is vertical? Write an expression for the momentum of the bob as a function of the angle theta the pendulum makes with the vertical.

Solution

There are number of questions, So I am answering first one.

h=12m m1=.5kg m2=2.5kg

At height the masses only have potential energy. At ground it only has kinetic energy as height h=0 at ground

Applying law of conservation of energy mgh=mv²/2 =>v = sqrt(2*g*h)=15.5m/s downward direction. I have taken g=10m/s²

^{momentum of mass 1 P1 = m1v=7.75kg.m/s(}downward direction^{) =>p2=m2v=38.75kg.m/s(downward direction)}