An electron of mass m and a photon have the same energy E. Find the ratio of de-Broglie wavelength associated with the electron to that associated with the photon. (c is the velocity of light)
1. (E2m)1/2
2. c(2mE)1/2
3. 1c(2mE)1/2
4. 1c(E2m)1/2
A radiation of energy 'E' falls normally on a perfectly reflecting surface. The momentum transferred to the surface is (c=velocity of light)
1. E/c
2. 2E/c
3. 2E/c2
4. E/c2
Which of the following figures represents the variation of the particle momentum and the associated de-Broglie wavelength?
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Light with a wavelength of 500 nm is incident on a metal with a work function of 2.28 eV. The de Broglie wavelength of the emitted electron will be:
1. <2.8×10−10 m
2. <2.8×10−9 m
3. ≥2.8×10−9 m
4. <2.8×10−12 m
Light with an energy flux of 25×104 Wm−2 falls on a perfectly reflecting surface at normal incidence. If the surface area is 15 cm2, then the average force exerted on the surface is:
1. 1.25×10−6 N
2. 2.5×10−6 N
3. 1.2×10−6 N
4. 3.0×10−6 N
What will be the percentage change in the de-Broglie wavelength of the particle if the kinetic energy of the particle is increased to 16 times its previous value?
1. 25
2. 75
3. 60
4. 50