Figure shows a ray of light meeting the glass of the window of a car at angle of incidence of 30c.
i. Assuming that the refractive index of glass is 1.5, find the angle of refraction for this ray in the
glass. (Given : sin 1( . 9 5c) / = 1 3)
ii. Complete the diagram by sketching the path of the ray through the glass and out on the other
side.
Answers
Answer:
Explanation:
y=cos
−1
(cos10) and x=sin
−1
(sin10)
answer is not zero , it means here 10 is in radian not in degree.
so, 10=
π
10π
=
(22/7)
10π
=
22
70π
=
11
35π
=
11
(33π+2π)
=3π+
11
2π
we know, y=cos
−1
(cosA)=A if 0<A<π
see graph of cos
−1
(cosx)
here it is clear that, graph between 3π to 4π
so, equation of line between 3π to 4π :
Y−π=
(4π−3π)
(0−π)
(X−3π)
Y−π+(X−3π)=0
X+Y−4π=0
so, Y=4π−X
so, y=cos
−1
(cos10)=4π−10
again, for x=sin
−1
(sin10) see graph, between 3π to
2
7π
[ because 3π+
11
2π
lies between them ]
here, equation of line lies between 3π to
2
7π
points are (
2
5π
,
2
π
) and (
2
7π
,
2
−π
) is
Y+
2
π
=
(
2
7π
−
2
5π
)
(
2
−π
−
2
π
)
(X−
2
7π
)
Y+
2
π
+(X−
2
7π
)=0
Y+X−3π=0
Y=3π−X
hence, x=sin
−1
(sin10)=3π−10
now, y−x=4π−10−(3π−10)=π
hence, answer should be π
During the 19th century, nationalism emerged as a force which brought about
changes like the emergence of the nation-states in place of the different dynastic
empires of Europe. In 1848, Frederic Sorrieu, a French artist, visualised world as
democratic and social
republics.
The first idea of nationalism came with the French Revolution in 1789. French
Revolution led to the transfer of sovereignty from the monarchy to a body of Frenc
citizens.
The French revolutionaries introduced various measures and practices that could
create a sense of collective identity amongst the French people. The French
Revolution introduced new ideas like la patrie (the fatherland) and le citoyen (the
citizen) and a new French flag replacing the former royal standard amongst the
French people. It introduced a centralised administrative system with uniform law
for all citizens.
Other measures were new hymns were composed and oaths were taken, martyrs
were remembered in the name of the nation,
internal customs duties and dues we
abolished and Estates General was elected by the body of citizens and renamed as
National Assembly. Regional dialects were discouraged. French language for
speaking and Paris language for writing were accepted as a common language of t
country.