Question

11. A mark on the surface of a glass sphere (u = 1.5) is viewed from a
diametrically opposite position. It appears to be at a distance 10 cm from
its actual position. The radius of the sphere is ___ cm.​

Answer 1

At a distance 10 cm from  its actual position. The radius of the sphere is given below :-

Explanation:

A mark on the surface of a glass sphere :

u1 = 1.5

Distance from  its actual position:

10 cm

u2 = 2R

V = 10 - 2R

u2 / V - u1 / U = u2 - u1 / R                                           ,    u2 =1

1 /( 10 - 2R ) - 1.5 / -2R = 1 - 1.5 /-R                                  ,    u1 = u = 1.5

1 / ( 10 -2R ) + 3 / 4R = 1 / 2R  

=> 1 / 10 - 2R = 1 / 2R - 3 / 4R  

=> 1 / 10 - 2R = -1 / 4R

4R = 2R - 10

2r = -10

R = -5 cm

R = 5 cm

For more:

1. The radius of a sphere is 5 cm. Calculate the radius of gyration about it's diameter and about any yangent.

https://brainly.in/question/1933979

2. If radius of the sphere is 14 cm. If the radius is increased by 50%find how much % is the volume increased ?

https://brainly.in/question/1112150