The wavelength emitted is indirectly proportional to the difference in the change in the energy level. For the wavelength 278 nm the change in energy level is significantly high. Further change in energy level is indicated by 454nm light but the difference in energy level for this wavelength to be emitted is not greater than the previous one. There is a possibility that these subsystems have now very low energy which should result in wavelengths ranging from 700 to 900 nm. There is another possibility that there is some metastable subsystems in the system which may cause LASER emission.
Answer:
she is pulling with 40 N force
Explanation:
The ring does not move means that the forces are equal.
Let's call Jo's force x
We have the quation
140 = x + 100
x = 40
Answer:

Explanation:
Those kind of problems of electric physics is about capacitors, so the normal questions are:
What are the charge on each electrode?
Solve this you can get other information required in the problem or write down the other questions you need


Capacitance





The charge is find by the equation



Answer:
Work done, W = 84.57 Joules
Explanation:
It is given that,
Mass of the wooden block, m = 2 kg
Tension force acting on the string, F = 30 N
Angle made by the block with the horizontal, 
Distance covered by the block, d = 3 m
Let W is the work done by the tension force. It can be calculated as :


W = 84.57 Joules
So, the work done by the tension force is 84.57 Joules. Hence, this is the required solution.