Bob Joe asked in Science & MathematicsPhysics · 9 years ago

# A cart of mass M1 = 4.0 kg and initial speed of 3.0 m/s collides head-on with a second cart of mass M2 = 2.0 k?

A cart of mass M1 = 4.0 kg and initial speed of 3.0 m/s collides head-on with a second cart of mass M2 = 2.0 kg at rest. Assuming that the collision is elastic, find the speed of M2 after the collision.

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• Anonymous
9 years ago

Conserve momentum and kinetic energy.

You will have two unknowns v1 (the final velocity of M1) and v2 (the final velocity of M2).

Conserving momentum and kinetic energy will give you two equations.

Two equations, two unknowns, you have it solved!

Momentum = p = mv

Kinetic energy = 1/2 m v^2

Initially only one car has momentum and only one car has kinetic energy. You are given both mass and velocity. So, you can easily find the initial momentum and kinetic energy using the equations above.

After the collision, both masses having momentum and kinetic energy. You will have to use the v1 and v2, because you do not know the final velocities.

Now conserved momentum and kinetic energy. You know that means, don't you? Set the initial momentum equal to the final momentum and set the initial kinetic energy equal to the final kinetic energy.

This gives you the two equations with two unknowns. This is now a simple math problem. So solve it!

• bianca
Lv 4
4 years ago

locate velocity by way of: v = (m1 * v1) + (m2 * 0) / (m1 + m2) v = ((3.2 * 2.a million) + 0) / (7.5) v = 0.896 m/s Then subtract that velocity from the preliminary velocity to locate the rate of m1 interior the middle of mass physique after the collision: vf* = (2.1m/s) - (0.896m/s) vf* = -a million.204m/s (that's unfavorable with the aid of fact after the collision it strikes interior the unfavorable direction)