Two objects, each of mass 2 kg, are moving in the same straight line but in opposite directions. They are moving with velocities 10 m/s and 5 m/s respectively before the collision during which they stick together. The velocity of the combined object after collision is,

2.5m/s

Explanation:

Using the law of conservation of energy;

m1u1 + m2u2 = (m1+m2)v

m1 and m2 are the masses

u1 and u2 are the initial velocities

v is the final velocity

Substitute the given values in the formula

2(10)-2(5) = (2+2)v

20-10 = 4v

10 = 4v

v = 10/4

v = 2.5m/s

Hence the velocity of the combined object after collision is 2.5m/s

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