1. Two objects of mass 0.2 kg and 0.1 kg, respectively move parallel to the x-axis. The 0.2 kg object overtakes and collides with the 0.1 kg object. Immediately after the collision, the y-component of the velocity of the 0.1 kg is 1 m/s upward. What is the y-component of the velociy of the 0.1 kg object immediately after the collision?(adsbygoogle = window.adsbygoogle || []).push({});

a. 2 m/s

b. .5 m/s downward

c. 0 m/s

d. .5 m/s upward

e. 2 m/s upward

0.2 kg O-------->

---------0.1 kg 0---->

This is probably an easy one; the answer is not 0 m/s. Can anyone explain to me how to go about getting the answer and why 0 m/s is not the answer?

2. 2 people of unequal mass are initially standing still on ice with negligible friction. They then simultaneously push each other horizontally. Afterward, which is true?

a. The kinetic energies of the 2 people are =.

b. Speeds of 2 people are =.

c. Momenta of 2 people are of = magnitude.

d. Center of mass of 2-person system moves in the direction of less massive person.

e. Less massive person has a smaller initial acceleration than more massive person.

A and B are incorrect, but I have no idea why. Could anyone explain to me why the correct answer answer is correct and the incorrect ones are incorrect?

Thanks for clearing these up.

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# Homework Help: Momentum and collision physics Question

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