Answer:
Intensity, 
Explanation:
Power of the light bulb, P = 40 W
Distance from screen, r = 1.7 m
Let I is the intensity of light incident on the screen. The power acting per unit area is called the intensity of the light. Its formula is given by :




So, the intensity of light is
.
Answer:
The number of turns in secondary coil is 4000
Explanation:
Given:
Current in primary coil
A
Current in secondary coil
A
Number of turns in primary coil 
In case of transformer the relation between current and number of turns is given by,

For finding number of turns in secondary coil,



Therefore, the number of turns in secondary coil is 4000
As we know that when charge is released in electric field
It will have two forces on it
1. electrostatic force
2. gravitational force
now if the ball will accelerate upwards so we can say
net upward force = mass * acceleration


now we can find charge q on it by above equation

So above is the charge on the particle
The statement about "<span>efficiency compared the output work to the output force" is false. Efficiency can be compared from the input work to the output work.</span>
Well a Electron capture is, <span> one process that unstable atoms can use to become more stable. :) Hope this helps if ya want subscribe to my YouTube it's Enstanding tysm!</span>