Question

Select the correct answer.

Before a collision, the x-momentum of an object is 8.0 × 103 kilogram meters/second, and its y-momentum is 1.2 × 104 kilogram meters/second. What is the magnitude of its total momentum after the collision?
A.
1.4 × 104 kilogram meters/second
B.
2.0 × 104 kilogram meters/second
C.
3.2 × 104 kilogram meters/second
D.
5.7 × 104 kilogram meters/second

Answer 1

We can use the Pythagorean theorem to find the magnitude of the total momentum:

total momentum = sqrt[(x-momentum)^2 + (y-momentum)^2]

total momentum = sqrt[(8.0 × 10^3)^2 + (1.2 × 10^4)^2]

total momentum = sqrt[6.4 × 10^7 + 1.44 × 10^8]

total momentum = sqrt(2.08 × 10^8)

total momentum ≈ 1.44 × 10^4 kilogram meters/second

Therefore, the correct answer is A. 1.4 × 10^4 kilogram meters/second.