Advanced Geometry by H.C. Rajpoot
Q.1.An electric bulb of 200 W is mounted onto the centre of one of the walls of
a room of Find out the total radiation energy striking the
floor area if the bulb emits radiation uniformly in all the directions.
(Neglect height of bulb from the centre of wall) Ans. 21.788 J/sec
Q.2.A uniform point-source of light is located at the centre of a torus having
inner & outer radii 10cm & 18cm respectively. What will be the fraction of total
radiation intercepted by the torus? Ans. ⁄
Q.3.A torus intercepts of the total radiation emitted by a uniform point-
source located at the centre of torus. Find out ratio of outer to inner radii of
torus. Ans. ⁄
Q.4.A solar-panel of is illuminated by a uniform point-source of
light located at a normal height 15√√ from the centre of panel.
Find out percentage of total radiation incident on panel. Ans.
Q.5. Find out the solid angle subtended by an infinitely long vertical cylindrical
pole with a diameter D at a point lying in the plane of base at a normal
distance 2D from the longitudinal axis. Ans. ⁄
Q.6.A torus having diameter 8cm intercepts of the total radiation emitted
by a uniform point-source located at the centre of torus. Find out inner &
outer radii of torus. Ans. 14cm & 6cm
Q.7.A uniform point-source of light is located at a normal height 8cm from the
centre of an infinitely long rectangular plane having width 16cm. What will be
the percentage of total radiation intercepted by the plane? Ans.
Q.8.Some identical spheres are arranged, touching one another, in a complete
circular fashion such that each of them intercepts of total radiation
emitted by a uniform point-source located at the centre of polygonal plane
obtained by joining the centres of spheres. Find out number of spheres. Ans. 3