How far away can two point sources of light of wavelength 500 nm be, if they are just resolvable in a telescope with an aperture width of 1.5 cm?

25 km

12 km

90 m

12 m

more information is needed

An innovative physics professor conducts laboratory exercises in the college swimming pool. The professor places a submersible laser under water (n = 1.3) and aims the beam at a block of glass (n = 1.5), which is also under water. At what angle of incidence will the reflected beam be totally polarized?

61°

49°

41°

39°

For electromagnetic radiation of intensity of 1.00 W/m², what is the rms value of the electric field?

19.4 V/m

9.69 V/m

6.45 × 10^-8 V/m

9.11 × 10^-8 V/m

3.00 × 10⁷ V/m

An ac circuit consists of a 220 mH inductor in series with a 75 kΩ resistor and a 12 V rms sinusoidal emf. If the frequency of the emf is 25 kHz, what is the rms voltage across the resistor?

7.0 V

9.4 V

11 V

5.0 V