Answer:
(a) 
(b) 
(c) 
Explanation:
(a) The orbital period is the time that the electron spend to travel the orbit of the atom. Thus, it is given by the length of the circular orbit divided by its velocity:

(b) Current means charge over time, So, in this case is charge over period:

(c) Magnetic moment is given by:

Here A is the area of the orbit.

The interaction of electric currents or fields and magnetic fields.
Ans. 5 X 10^6
Explanation:
Here,^ represents 6 times 10 and 5 is multiplied. That is 5000 000.
Hope this helps
During a total lunar eclipse, the Moon located in the umbra.
The answer is letter A. For a total lunar eclipse to occur, the Sun, Earth and
Moon must be aligned in a straight line. The Earth’s umbra complete covers the
Moon. The earth’s umbra is about 870,000 miles wide.
Answer:
Explanation:
When 238U which is radioactive turns into 206Pb , it becomes stable and no further disintegration is done . Hence in the initial period ratio of 238U undecayed and 206Pb formed will be very high because no of atoms of 238U in the beginning will be very high. Gradually number of 238U undecayed will go down and number of 206Pb formed will go up . In this way the ratio of 238U and 206Pb in the mixture will gradually reduce to be equal to one or even less than one .
In the given option we shall calculate their raio
1 ) ratio of 238U and 206Pb = 5
2 ) ratio of 238U and 206Pb = 4
3 )ratio of 238U and 206Pb = 1
4 ) ratio of 238U and 206Pb = 20
5 )ratio of 238U and 206Pb = 3
lowest ratio is 1 , hence this sample will be oldest.
Ranking from youngest to oldest
4 , 1 , 2 , 5 , 3 .