Can you help me understand this question in detail with step-by-step methods and
ID: 1564456 • Letter: C
Question
Can you help me understand this question in detail with step-by-step methods and, the formula that is being used so that, I can understand better.
A 2.0-kg cart moving to the right with a speed of 6.0 m/s has a head-on collision with a 5.0-kg cart that is initially moving to the left with a speed of 2.0 m/s. After the collision, the 2.0-kg cart is moving to the left with a speed of 3.0 m/s. What is the final velocity of the 5.0-kg cart?
(a) 0.80 m/s to the left (c) zero m/s (e) 1.2 m/s to the left (b) 0.80 m/s to the right (d) 1.2 m/s to the right
Explanation / Answer
Using momentum conservation:
Pi = Pf
m1u1 + m2u2 = m1v1 + m2v2
right side is +ve and left side is -ve
u1 = +6 m/sec
u2 = -2 m/sec
v1 = -3 m/sec
So,
2*6 - 5*2 = -2*3 + 5*v2
v2 = 8/5 = +1.6 m/sec
+ve sign means towards the right
Correct answer should be +1.6 m/sec to the right, which is not given in any option.
Please check the question again and let me know if there is a mistake in any given value.