A diffraction pattern is observed using a beam of red light. What will happen if the red light is replaced by the blue light?

The first diffraction minima due to a single slit diffraction is at $\mathrm{\theta } = 30°$for a light of wavelength  \(5000~\mathring A.\)  The width of the slit is:

1. 5 x 10^-5 cm

2. 10 x 10^-5 cm

3. 2.5 x 10^-5 cm

4. 1.25 x 10^-5 cm

What will be the angular width of central maxima in Fraunhofer diffraction when the light of wavelength \(6000~\mathring A\) is used and slit width is $12\times {10}^{-5}\mathrm{cm}$?

1. 2 rad

2. 3 rad

3. 1 rad

4. 8 rad

Red light is generally used to observe diffraction patterns from a single slit. If the blue light is used instead of red light, then the diffraction pattern:

If we observe the single slit Fraunhofer diffraction with wavelength $\mathrm{\lambda }$ and slit width d, the width of the central maxima is 2$\mathrm{\theta }$. On decreasing the slit width for the same wavelength $\mathrm{\lambda }$:

A parallel beam of monochromatic light of wavelength 5000 Å is incident normally on a single narrow slit of width 0.001 mm. The light is focused by a convex lens on a screen placed on the focal plane. The first minimum will be formed for the angle of diffraction equal to:

1. 0^o

2. 15^o

3. 30^o

4. 60^o

In a diffraction pattern due to a single slit of width \(a\), the first minimum is observed at an angle of \(30^{\circ}\) when the light of wavelength \(5000~\mathring{\text{A}}\) is incident on the slit. The first secondary maximum is observed at an angle of:
1. \(\text{sin}^{-1}\frac{2}{3}\)
2. \(\text{sin}^{-1}\frac{1}{2}\)
3. \(\text{sin}^{-1}\frac{3}{4}\)
4. \(\text{sin}^{-1}\frac{1}{4}\)

The direction of the first secondary maximum in the Fraunhofer diffraction pattern at a single slit is given by:
(a is the width of the slit) 

1. $a\sin \theta =\frac{\lambda }{2}$

2. $a\cos \theta =\frac{3\lambda }{2}$

3. $a\sin \theta =\lambda$

4. $a\sin \theta =\frac{3\lambda }{2}$

A single slit of width 0.1 mm is illuminated by a parallel beam of light of wavelength 6000 $\stackrel{0}{\mathrm{A}}$ and diffraction bands are observed on a screen 0.5 m from the slit. The distance of the third dark band from the central bright band is:

1. 3 mm

2. 9 mm

3. 4.5 mm

4. 1.5 mm

A parallel beam of moving electrons is incident normal on a narrow slit. A fluorescent screen is placed at a large distance from the slit. If the slit is further narrowed, then which of the following statements is correct?