Answer:
option E
Explanation:
given,
diameter = 4 mm
shutter speed = 1/1000 s
diameter of aperture = ?
shutter speed = 1/250 s
exposure time to the shutter time

N is the diameter of the aperture and t is the time of exposure
now,


inserting all the values

N₂² = 4
N₂ = 2 mm
hence , the correct answer is option E
Answer:
The standard of efficiency varies by product category
these are called BEE star label and they show how much electricity the appliance consumes in year each appliance gets btw one and five stars with five stars meaning that it's extremely efficienct andis likely to keep your electricity bills in check
<em><u> </u></em><em><u>hop</u></em><em><u>e</u></em><em><u> it's</u></em><em><u> helpful</u></em>
He reasoned that since parallax could not be observed for celestial objects near the sun, then the earth was stationary. This erroneous assumption was because at the time he had no way of knowing that celestial objects were so far away that their parallax angles were too small to detect.
1. The property of a conductor by virtue of which it posses the flow of electric current through it is called resistance.
2. The resistance of a conductor depends on the cross sectional area of the conductor and it's resistivity.
3.This id due to the fact that the resistance of a wire is inversely proportional to the square of its diameter.
4.Due to at high temperatures , the alloy donot oxidize. Alloy doesn't melt readily and get deformed.