Sheela was a student. One day, she saw that rainbow appears in the sky after raining. Another day, when she was drying her hairs in sunlight, she found the same combination of colour, by watching the sunlight through her hairs. She was very surprised but confused also. She asked about this from her science teacher who satisfied her by telling about the composition of light (white light) and its splitting into different colours when passed through different medium.
(a) Give the composition of white light?
(b) Can you guess why she saw a phenomenon similar to formation of rainbow when light passed through her hair?
(c) Applying Bohr's model when electrons in H-atom comes from n = 4 to n = 2, m calculate the wavelength of the line.
\(\left( { R }_{ H }=2.18\times { 10 }^{ -18 }J, \ h=6.63\times { 10 }^{ -34 }J \right) \).
(d) What values are associated with Sheela's teacher?

Romi is a class XI student. One day he studied Heisenberg's uncertainty principle, according to which it is not possible to determine the exact position and velocity of a moving object simultaneously. But when he was watching car race, he found that it is possible to measure position and velocity of a car at any instance simultaneously. He got confused. He asked this to his father. His father clarified his doubt. From his answer, he got satisfied.
(a) What thing is missing in the above given statement of Heisenberg's principle?
(b) Can you guess the clarification given by Romi's father?
(c) What values are exhibited by Romi and his father?