Practice-Quiz5-1

Practice-Quiz5-1 - What about just after? Explain briefly....

Info iconThis preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
Physics 7B Practice Quiz 5 Grade: DL Section: Name: _______________________ ID: _______________________ I certify by my signature that I will abide by the code of academic conduct of the University of California. Signature No books or notes. Calculators OK. Show all your work below. Answers alone do not receive credit! 1. You are riding your bike, and texting. Another student, riding her bike in the opposite direction, is also texting. You both have a speed of 3 m/s. You collide head on, and become a single, tangled mass. Fortunately you are wearing helmets so you are not seriously hurt. Your mass plus that of your bike is 60 kg. The other student’s mass, plus the mass of her bike, is 120 kg. (Big backpack.) a. (2.0 pts) What is the total momentum of the two of you plus bikes just before the collision?
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Background image of page 2
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: What about just after? Explain briefly. b. (2.5 pts) Draw a complete momentum chart (with actual numbers in the cells) of the situation before and after the collision. From it, determine the impulse the other student imparts to you ? momentum: p = m v impulse = change in momentum 2 Solution: a. Your total momentum is (60 kg)(3 m/s) = 180 kg-m/s. That of the other cyclist is 360 kg-m/s, but in the opposite direction. Thus the total momentum is 180 kg-m/s, in the direction of the other cyclist. b. We can write the momentum chart as follows: initial change fnal you other cyclist total 180 kg-m/s-240 kg-m/s-60 kg-m/s-360 kg-m/s +240 kg-m/s-120 kg-m/s-180 kg-m/s-180 kg-m/s Thus the impulse of the other student on you is -240 kg-m/s (that is, in the direction opposite your initial motion)....
View Full Document

This note was uploaded on 01/05/2011 for the course PHY 7B PHY7B taught by Professor Cebra during the Spring '10 term at UC Davis.

Page1 / 2

Practice-Quiz5-1 - What about just after? Explain briefly....

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online