A LASER is a source of very intense, monochromatic, and unidirectional beam of light. These properties of a laser light can be exploited

(a) Concave mirror as well as convex lens

The energy from the sun reaches the food chain through the primary producers (plants). This energy is passed on through successive trophic levels in the food chain. The energy transfer...

In a food chain the energy moves progressively through the various trophic levels and is no longer available to the organisms of the previous trophic level. The energy captured by...

The heat from interior of the earth can be utilised as a source of energy under certain favourable conditions that are created by natural processes. This is known as geothermal...

To get equally intense lines on the photographic plate, the radiant flux (energy) should be same. So, 10W × 12sec = 12W × t => t =10Wx12 sec/12W= 10 sec.

Overall luminous efficiency =Total luminous flux / Power input =35x685/100 = 239.75 lumen/W

(b) The luminous efficiency of a monochromatic source of wavelength 555 nm is always greater than that of a white light source of same power. (c) The illuminating power of a...

(a) towards the proton beam

(c) has all wavelengths greater than a certain minimum wavelength

λ  = 663 x 10–9 m,  θ= 60°, n = 1 x 1019, λ = h/p => P = p/λ = 10–27 Force exerted on the wall = n(mv cosθ –(–mv cosθ)) = 2n mv cos θ. = 2 x 1 x 1019 x 10–27...