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Discuss the possibility that star velocities at the edges of galaxies being greater than expected is due to unknown properties of gravity rather than to the existence of dark matter. Would this mean, for example, that gravity is greater or smaller than expected at large distances? Are there other tests that could he made of gravity at large distances, such as observing the motions of neighboring galaxies?
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Chapter 34 Solutions
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- choosing East (e) is not correct!arrow_forwarddisks have planes that are parallel and centered Three polarizing On a common axis. The direction of the transmission axis Colish dashed line) in each case is shown relative to the common vertical direction. A polarized beam of light (with its axis of polarization parallel to the horizontal reference direction) is incident from the left on the first disk with int intensity So = 790 W/m². Calculate the transmitted intensity if 81=28.0° O2-35.0°, and O3 = 40.0° w/m² horizontal Өз 02arrow_forwardA polarized light is incident on several polarizing disks whose planes are parallel and centered on common axis. Suppose that the transmission axis of the first polarizer is rotated 20° relative to the axis of polarization of the incident and that the transmission axis of each exis of light, additional analyzer is rotated 20° relative to the transmission axis the previous one. What is the minimum number of polarizer needed (whole number), so the transmitted light through all polarizing sheets has an Striking intensity that is less then 10% that the first polarizer?arrow_forward
- A high energy pulsed laser emits 1.5 nano second-long pulse of average power 1.80x10" W. The beam is cylindrical with 2.00 mm in radius. Determine the rms value of the B-field? -Tarrow_forwardA 23.0-mw (mill:-Watts) laser puts out a narrow cyclindrical beam 50 mm in diameter. What is the average N/C. rms E-field?arrow_forwardThe average intensity of light emerging from a polarizing sheet is. 0.550 W/m², and the average intensity of the horizontally polarized light incident on the sheet is 0.940 W/m². Determine the angle that the transmission axis of the polarizing sheet makes with the horizontalarrow_forward
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