A point source of light is placed at the centre of curvature of a hemispherical surface. The source emits a power of $$24 \mathrm{~W}$$. The radius of curvature of hemisphere is $$10 \mathrm{~cm}$$ and the inner surface is completely reflecting. The force on the hemisphere due to the light falling on it is ____________ $$\times~10^{-8} \mathrm{~N}$$.
Nearly 10% of the power of a $$110 \mathrm{~W}$$ light bulb is converted to visible radiation. The change in average intensities of visible radiation, at a distance of $$1 \mathrm{~m}$$ from the bulb to a distance of $$5 \mathrm{~m}$$ is $$a \times 10^{-2} \mathrm{~W} / \mathrm{m}^{2}$$. The value of 'a' will be _________.
The displacement current of 4.425 $$\mu$$A is developed in the space between the plates of parallel plate capacitor when voltage is changing at a rate of 106 Vs$$-$$1. The area of each plate of the capacitor is 40 cm2. The distance between each plate of the capacitor is x $$\times$$ 10$$-$$3 m. The value of x is __________.
(Permittivity of free space, E0 = 8.85 $$\times$$ 10$$-$$12 C2 N$$-$$1 m$$-$$2).
The intensity of the light from a bulb incident on a surface is 0.22 W/m2. The amplitude of the magnetic field in this light-wave is ______________ $$\times$$ 10$$-$$9 T.
(Given : Permittivity of vacuum $$\in$$0 = 8.85 $$\times$$ 10$$-$$12 C2 N$$-$$1-m$$-$$2, speed of light in vacuum c = 3 $$\times$$ 108 ms$$-$$1)