Question

In DESPERATE NEED OF HELP!!!

An object of mass m = 10 kg and speed v = 2 m/s collides head on with a second object of mass m = 5 kg which has a speed v = 1 m/s. The objects stick together. There are no external forces on the two objects (note the given "v"s are the speeds, not the velocities).

What is the final speed of the stuck-together masses?

(Fill in the blank): The final kinetic energy of the stuck together masses is _____ the sum of the initial kinetic energies of the two objects.
(A. equal to, B. less than, C. greater than?)

Answer 1

a. M1*V1 + M2*V2 = M1*V + M2*V.
10*2 - 5*1 = 10V + 5V. V = ?.

b. KE2 = 0.5M1*V^2 + 0.5M2*V^2. =
KE after collision.

c. KE1 = 0.5M1*V1^2 - 0.5M2*V2 = KE before collision.