please help with physics?

A 1.5 kg cart moving right at 2 m/s collides totally inelastically with a 2 kg cart moving left at 2 m/s. Determine loss to thermal energy.

Mugwump2014-02-10T18:55:51Z

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Hello Mike,

FIrst calculate the final velocity of the two carts stuck together. The mass of cart one is m1 and the mass of cart 2 is m2. The initial velocity of cart one is u1 and the initial velocity of ccart tow is u2. The final velocity of the two carts stuck together is V.

So from the law of momentum.

m1u1 + m2u2 = (m1 + m2)V

V = (m1u1 + m2u2)/(m1 + m2)

V = (1.5 kg * 2 m/s + 2.0 kg * - 2 m/s)/(1.5 kg + 2 kg)

V = - 0.29 m/s

Now use the conservation of energy to check for losses.

Initial KE = Final KE + thermal losses.

thermal losses = initial kE - Final KE

Initial KE = (1/2) m1 u1^2 + (1/2) m2 u2^2

Final KE = (1/2) (m1 + m2) V^2

Good Luck Mike