Question

Numericals:
1. The wavelength of light of a particular co
5800 A. Express it in (a) nanometre and (b) metre
Ans. (a) 580 nm, (b) 5.8 x 10-7m
2. The size of a bacteria is 1 u. Find the number
bacteria in 1 m length.
3. The distance of a galaxy from the earth is 5-6 x 1028
Assuming the speed of light to be 3 x 108 m
find the time taken by light to travel this distance
Ans. 106
81
[Hint : Time taken - Distance travelled
speed
5.
Ans. 1-87 x 1017
4. The wavelength of light is 589 nm. What is ite
wavelength in A ?
Ans. 5890 Å
The mass of an oxygen atom is 16.00 u. Find its masa
in kg
Ans. 2:656 x 10-26 ko
6. It takes time 8 min for light to reach from the sun to
the earth surface. If speed of light is taken to be
3 x 108 m s 1, find the distance from the sun to the
earth in km.
Ans. 1-44 x 108 km
"The distance of a star from the earth is 8.33 light
minutes.' What do you mean by this statement ?
Express the distance in metre. Ans. 1.5 x 1011 m
​

Answer 1

Answer:

1.5

Explanation:

1.5*41