Given data
*The mass of cart 1 is 2.5 kg
*The mass of cart 2 is 4 kg
*The speed of the cart 1 before the collision is 5 m/s
*The speed of the cart 2 before the collision is -1.5 m/s
*The speed of the cart 2 after the collision is 3 m/s
The formula for the velocity of the cart 1 is given by the conservation of momentum as
Substitute the known values in the above expression as
Thus, the velocity of Cart 1 after the collision is -2.2 m/s and the correct answer is (C)