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
.
Hey girl
the answer is A
your correct the atmosphere provides warmth
hope this helps
XD
The magnitude of the magnetic force per unit length on the top wire is
2×10⁻⁵ N/m
<h3>How can we calculate the magnitude of the magnetic force per unit length on the top wire ?</h3>
To calculate the magnitude of the magnetic force per unit length on the top wire, we are using the formula
F= 
Here we are given,
= magnetic permeability
= 4
×10⁻⁷ H m⁻¹
If= 12 A
d= distance from each wire to point.
=0.12m
Now we put the known values in the above equation, we get
F= 
Or, F = 
Or, F= 2×10⁻⁵ N/m.
From the above calculation, we can conclude that the magnitude of the magnetic force per unit length on the top wire is 2×10⁻⁵ N/m.
Learn more about magnetic force:
brainly.com/question/2279150
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