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Question 26 of 36

An object with mass $m$ and speed $v_{0}$ directed to the right strikes a wall and rebounds with speed $v_{0}$ directed to the left.

The change in the object's momentum is

Select an Answer

$2 m invisible times text end text v subscript 0$ directed to the left

Correct Answer:

Yes

$m invisible times text end text v subscript 0$ directed to the left

Correct Answer:

No

$text Zero end text$

Correct Answer:

No

$m text end text v subscript 0$ directed to the right

Correct Answer:

No

$2 m invisible times text end text v subscript 0$ directed to the right

Correct Answer:

No

View Correct Answer

The change in the object's momentum is $2 m v_{0}$ directed to the left. Momentum is a vector quantity. Its magnitude for an object of mass $m$ and speed $v$ is $m v$ . Taking the positive direction to be to the right (the initial direction of the object), the object has momentum $+ m v_{0}$ before striking the wall and momentum $- m v_{0}$ afterward. The change in momentum is the final value minus the initial value: $- m v_{0} - (+ m v_{0}) = - 2 m v_{0}$