Question

I have Part C and E left ??how to do it ?

Consider light from a helium-neon laser (λ=632.8 nanometers) striking a pinhole with a diameter of 0.160 mm . Part A At what angle θ1 to the normal would the first dark ring be observed?

θ1 = 0.276 ∘ Correct

Part B

Suppose that the light from the pinhole projects onto a screen 3.00 meters away. What is the radius r1 of the first dark ring on that screen? Notice that the angle from Part A is small enough that sinθ≈tanθ.

r1 = 14.5 mm Correct

Part C

The first dark ring forms the boundary for the bright Airy disk at the center of the diffraction pattern. What is the area A of the Airy disk on the screen from Part B? Express your answer in mm2, to three significant figures.

A = (mm2 )

Diffraction due to a circular aperture is important in astronomy. Since a telescope has a circular aperture of finite size, stars are not imaged as points, but rather as diffraction patterns. Two distinct points are said to be just resolved (i.e., have the smallest separation for which you can confidently tell that there are two points instead of just one) when the center of one point's diffraction pattern is found in the first dark ring of the other point's diffraction pattern. This is called Rayleigh's criterion for resolvability.

Consider a telescope with an aperture of diameter 0.900 m .

Part D

What is the angular radius θ1 of the first dark ring for a point source being imaged by this telescope? Use 550 nanometers for the wavelength, since this is near the average for visible light.

Express your answer in degrees, to three significant figures.

θ1 =

4.27×10−5

∘

Part E

Two stars in a certain binary star system have angular separation of 5×10−5 degrees when viewed from earth. Can they be resolved with the telescope described above?

Two stars in a certain binary star system have angular separation of  degrees when viewed from earth. Can they be resolved with the telescope described above?

yes

no

Answer 1

E) Twe