Mentoring Content for 10-18-2023

Mentoring

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welcome to mentoring week whatever Paul Lea

Have a discussion about goals Talk about the S.M.A.R.T worksheet Registration advising - Whole physics dept gets together and listens to Dr Giedt talk classes - Oct 31st at 4 pm @ Amos Eaton 214 - Show ‘students how to use Quacs/SIS/Degreeworks - Make sure nobody has blocks for registration - Financial Agreement!! - HASS pathways, should take an IHSS this semester or next. - Talk about your own HASS pathway

Drop Deadline this Friday Quantum Physics quick fun notes -Quantum Physics 1 is now just Quantum Physics. Being taught by Persans next semester apparently. Quacs is questionable currently. -Quantum Physics 2 does not exist anymore, renamed to Applications of Quantum Physics. Not official yet.

Questions about assignments?

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Technical Problems: #1 Galilean Frame Practice (classical) Observer A sits by the side of the road. A bus carrying observer B tavels East on the road at a speed of 30 miles per hour. A car carrying Observer C travels east on the road at 40 miles per hour. Each observer can only see the other observers (not the ground).

A. Describe the motions of the three observers as seen by observer A B. Describe the motions of the three observers as seen by observer B C. Describe the motions of the three observers as seen by observer C.

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Calculate the Lorentz Factor for each of the following:

V = 1/2 c V = 870 mph V = 1240 m/s V = 3.2 gigafurlongs/fortnight (optional)

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A rocket flies between two planets that are 1 light year (in the planets reference frame) apart. What should the rockets speed be so that the time elapsed on the rocket captain’s watch is one year?

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The average lifetime of a π meson in its own frame of reference is 26.0 ns. (This is its proper lifetime.) •If the π meson moves with speed 0.95c with respect to the Earth, what is its lifetime as measured by an observer at rest on Earth? •What is the average distance it travels before decaying as measured by an observer at rest on Earth?

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Solution We take the S frame to be attached to the Earth and the S′ frame to be the rest frame of the π meson. It follows from $∆t=\gamma ∆t\prime$ that $∆t=83.3ns$ when $∆t\prime =26.0ns$ and $v=0.95c.$ The average distance traveled before decaying as measured by an observer at rest on Earth is $v∆t=24.0m.$

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An atomic clock is placed in a jet airplane. The clock measures a time interval of 3600 s when the jet moves with speed 400 m/s. •How much larger a time interval does an identical clock held by an observer at rest on the ground measure?

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We take the S frame to be attached to the Earth and the S′ frame to be the rest frame of the atomic clock. It follows from $\gamma =\frac{1}{\sqrt{1-{\beta }^2}}$ that $\gamma \approx 1+{\beta }^2/2$ and from $∆t=\gamma ∆t\prime$that $\delta t=∆t-∆t{\prime }^{\prime }\beta 2∆t\prime /2$ It follows that $\delta t=3.2$ ns when $v=400$ m/s and $∆t\prime =3600$s