A combination of two prisms, one of flint and other of crown glass produces dispersion without deviation. The angle of flint glass prism is `15^@`. Calculate the angle of crown glass prism and angular separation of red and violet rays on emergence from the spectroscope. (`mu` for crown glass `= 1.52, mu` for flint glass `= 1.65, omega` for crown glass `= 0.02, omega` for flint glass `= 0.03`).
Text Solution
Verified by Experts
Here, `A = 15^(@), A' = ?, omega = 0.03` `omega' = 0.02, mu = 1.65, mu' = 1.52` For no devitaion, `delta + delta' = 0` `(mu - 1)A + (mu' + 1)A' = 0` `(1.65 - 1)15^(@) + (1.52 - 1)A'= 0` `A' = (-0.65 xx 15)/(0.52) = - 18.75^(@)` Negative sign indicates that two prism must be joined in opposition. Net angular separation `= (mu_(v) - mu_(r )A + (mu_(v)' - mu_(r )')A'` `= omega(mu -1)A + omega' (mu' - 1)A'` `= 0.03(1.65 - 1)15^(@) + 0.02(1.52 - 1)(- 18.75^(@))` `= 0.2925 - 0.195` `= 0.0975^(@)`
Topper's Solved these Questions
OPTICS
PRADEEP|Exercise Very short answer question|5 Videos
OPTICS
PRADEEP|Exercise very short answer questions|1 Videos
A crown glass prism and a flint glass prism are combined to produce dispersion without deviation. Mean refractive indices of crown , and flint glass are respectively 1.5 and 1.6. Ratio of angle of crown glass prism to that of flint prism is
Determine the angle of flint glass prism, which should be combined with a crown glass prism of 5^@ so as to give dispersion, but no deviation. Given for crown glass, mu_v = 1.523, mu_r 1.515 For flint glass, mu_v' = 1.688, mu_r' = 1.650 .
Find the angle of the flint glass prism which should be combined with a crown glass prism of 6^@ so as to give dispersion but no deviation. For crown glass, mu_(v)=1.520, mu_(R)=1.48 For flit glass, mu_(v)=1.78,mu_(R)=1.72
The angle of crown glass (mu=1.52) prism is 5^(@) .What should be angle flint glass (mu=1.63) .Prism ,so that the two prism may be used in direct vision spectroscope?
Find the angle of flint glass prism which produces the same angular dispersion for c and F wavelengths in 10^(@) crown glass prism. For crown glass : mu_(F) = 1.5230, mu_( c) = 1.5145 For flint glass : mu'_(F) = 1.6637, mu'_( c) = 1.6444 .
The net angular dispersion produced without deviation for crown glass (mu = 1.56) and flint glass ( mu = 1.7) is
A crown glass prism of refracting angle 6^@ is to be achromatised fro red and blue light using a flint glass prism. Find the angle of flint glass prism and also, the mean deviation from the following data :
Flint glass prism is joined by a crown glass prism to produce dispersion without deviation. The refractive indices of these for mean rays are 1.602 and 1.500 respectively. Angle of prism of flint prism is 10^(@) , then the angle of prism for crown prism will be
The respective angles of the flint and crown glass prisms are A' and A. They are to be used for dispersion without deviation, then the ratio of their angles A'//A will be
