Which principle states that every point on a wavefront acts as a source of secondary wavelets?

A. Newton's principle

B. Huygens' principle

C. Doppler's principle

D. Fermat's principle

The central maximum in a single-slit diffraction pattern is observed to be wider than the subsequent maxima. What is the primary reason for this?

A. Interference of waves

B. Polarisation of light

C. Dispersion of light

D. Geometry of the slit

Which of the following factors will increase the width of the central maximum in a single-slit diffraction pattern?

A. Decreasing the slit width

B. Increasing the frequency of light

C. Decreasing the screen distance

D. Increasing the speed of light

For a single-slit diffraction pattern, the first minimum occurs when the path difference between waves from the top and bottom of the slit is:

A. λ/2

B. λ

C. 2λ

D. 3λ/2

If the wavelength of light used in a single-slit diffraction experiment is doubled, the width of the central maximum will:

A. Remain the same

B. Halve

C. Double

D. Quadruple

a) What is Huygens' principle and how does it relate to diffraction? [3]

b) A single slit has a width of 0.5 mm. If monochromatic light of wavelength 650 nm is shone on the slit, what is the width of the central maximum on a screen 1.5 m away from the slit? [4]

a) How does the central maxima differ from the subsequent minima in a diffraction pattern? [3]

b) For a slit width of 0.2 mm and light of wavelength 500 nm, what is the angle to the first minima in the diffraction pattern? [3]

a) How does the width of the central maxima change with an increase in slit width in a single-slit diffraction pattern? [2]

b) In a single slit diffraction setup with a slit width of 0.3 mm, how does the width of the central maxima change if the wavelength of the light used is doubled? [3]

a) Explain Huygens' principle and its significance in understanding wavefronts. [3]

b) A single slit has a width of 0.5 mm. Monochromatic light of wavelength 650 nm is incident on the slit. Calculate the width of the central maximum on a screen placed 1.5 m away from the slit. [4]

c) How would the width of the central maximum change if the wavelength of the light used is decreased? [2]

a) Describe the difference between the central maxima and the subsequent minima observed in a diffraction pattern. [3]

b) What factors determine the position and width of the first minima in a diffraction pattern? [3]

c) If the slit width is increased, how does it affect the position of the first minima? [2]