Assignment 4

course Phy201

What does the major quiz cover up to i need to take it by the end of the week and wonder how many assigments i need to finish before i will be ready to take the first major quiz

The Major Quiz is assigned on the Assignments page around Assignment 9 or 10, I believe. Check the Assignments page. I would confirm the details for you but I can't access the College's pages this evening, probably related to storms.

An automobile traveling a straight line is at point A at clock time t = 4 sec, where it is traveling at 10 m/s, to point B at clock time t = 11 sec, where it is traveling at 20.5 m/s. Point A is 75 meters from the starting point and point B is 115 meters from the starting point. What are the average velocity and the average acceleration of the automobile during the specified time? What evidence is there that the acceleration is or is not uniform?

Vavg=Total distance/total time Based on this you take Vavg=(115m-75m)/11s-4s=5.714m/s now to find acceleration=‘dv/’dt so you take (20.5m/s-10m/sec)/11s-4s=1.5m/s/s for the acceleration. The evidence to determine if this is uniform is take the Vavg 5.71m/s multiply it by 2 then add it to the starting velocity. This gives you a number of 21.428 which should equal the final velocity but it is very close so I would assume it is not uniform since it does not equal the final velocity.

Very good, except that your test for uniformity of velocity isn't correct. Close, but the final velocity would be double the average, minus the initial velocity.

The basic idea is that if the v vs. t graph is linear, then the average velocity will be equal to the average of initial and final velocities. Not so here (ave of init and final is around 15 m/s) so accel isn't uniform.

Assignment 4

course

16:32:11Intro Prob 6 given init vel, accel, `dt find final vel, dist

If initial velocity is v0, acceleration is a and time interval is `dt, then in symbols what are the final velocity vf and the displacement `ds?

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'dt *a+v1=V2 for the final velocity

to find displacement 'ds=V1*'dt+.5(a*'dt^2)

confidence assessment: 3

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16:34:45

What is the displacement `ds associated with uniform acceleration from velocity v0 to velocity vf in clock time `dt?

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ok

confidence assessment: 1

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16:39:46

Describe the flow diagram we obtain for the situation in which we know v0, vf and `dt.

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V0 and Vf would be connected to Vave in the seond row also v0 and Vf would be connected to the 'dv then with the 'dt it would be connected to teh 'dv to obtain acceleration you can also obtain displacement with Vave and 'dt

confidence assessment: 3

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16:40:04

** Student Response: I think I really confused what information stood for what in the Force and Pendulum Experiment. However, I enjoy doing the flow diagrams. They make you think in a different way than you are used to. INSTRUCTOR NOTE: These diagrams are valuable for most people. Not all--it depends on learning style--but most. **

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okproblems.

self critique assessment: 3

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This looks good. Let me know if you have any questions. &#