course phy201 GՇɁa珚y~ڍassignment #005
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17:21:17 Intro Prob 6 Intro Prob 6 How do you find final velocity and displacement given initial velocity, acceleration and time interval?
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RESPONSE --> vf = v0 + (a*dt) ds = vAVG*dt vAVG=v0*2
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17:21:53 ** To find final velocity from the given quantities initial velocity, acceleration and `dt: Multiply `dt by accel to get `dv. Then add change in velocity `dv to init vel , and you have the final velocity**
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RESPONSE --> ok self critique assessment: 3
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17:24:57 Describe the flow diagram we obtain for the situation in which we know v0, vf and `dt.
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RESPONSE --> on the first line are the three know quantities of v0, vf, and dt. v0 and vf lead to vAVG. vAvg and dt lead to ds. v0,vf, lead to dv. dv and dt lead to a. confidence assessment: 3
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17:25:19 ** The flow diagram shows us the flow of information, what we get from what, usually by combining two quantites at a time. How we get each quantity may also be included. From vf and v0 we get `dv, shown by lines from vf and v0 at the top level to `dv. From vf and v0 we also get and vAve, shown by similar lines running from v0 and vf to vAve. Then from vAve and `dt we get `ds, with the accompanying lines indicating from vAve and `dt to `ds, while from `dv and `dt we get acceleration, indicated similarly. **
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RESPONSE --> ok self critique assessment: 3
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17:29:17 Principles of Physics and General College Physics Students: Prob. 1.26: Estimate how long it would take a runner at 10 km / hr to run from New York to California. Explain your solution thoroughly.
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RESPONSE --> assuming the distance from NY to CA to be 4800 km you would simply divide 4800 km by 10 km/hr = 480 hrs confidence assessment: 3
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17:29:36 It is about 3000 miles from coast to coast. A km is about .62 mile, so 3000 miles * 1 km / (.62 miles) = 5000 km, approximately. At 10 km / hr, the time required would be 5000 km / (10 km / hr) = 500 km / (km/hr) = 500 km * (hr / km) = 500 (km / km) * hr = 500 hr.
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RESPONSE --> ok self critique assessment: 3
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17:33:26 All Students: Estimate the number heartbeats in a lifetime. What assumptions did you make to estimate the number of heartbeats in a human lifetime, and how did you obtain your final result?
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RESPONSE --> assume lifespan of 70 years and a heartbeat of 70 beats per minute. 70 years*365 days/yr *24 hrs/day* 60 min/hr * 70 beats/min = 257 * 10^7 heartbeats in a lifetime. confidence assessment: 3
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17:33:58 ** Typical assumptions: At 70 heartbeats per minute, with a lifetime of 80 years, we have 70 beats / minute * 60 minutes/hour * 24 hours / day * 365 days / year * 80 years = 3 billion, approximately. **
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RESPONSE --> ok self critique assessment: 3
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17:34:21 University Physics Students Only: Problem 1.52 (i.e., Chapter 1, Problem 52): Angle between -2i+6j and 2i - 3j. What angle did you obtain between the two vectors?
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RESPONSE --> ok confidence assessment:
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