The main advantage of an electromagnet over a permanent magnet is that the magnetic field can be quickly changed by controlling the amount of electric current in the winding. However, unlike a permanent magnet that needs no power, an electromagnet requires a continuous supply of current to maintain the magnetic field.
B
paired electrons spin in opposite directions cancelling their magnetic fields
The most necessary condition to build a glacier is: <span>More snow must fall in the winter than melts in the summer.
</span><span>when More snow fall in the winter than it melts in the summer, the snow will start to accumulate on the top of the higher terrain. This accumulation will form an abundant amount of snow on higher terrain, which will fall as glacier as soon as its temperature drop.</span>
Answer:
the number of lines is 526
Explanation:
The wavelength λ =600nm = 600 × 10⁻⁶ mm
The diffraction angle θ = 39°
Recall the expression for the relation between the wavelength, angle and central maxima distance.
Recall the expression for the relation between the wavelength, angle and central maxima distance.
Recall the expression for the relation between the wavelength, angle and central maxima distance.
relation between the wave length, angle and central maxima distance
d = nλ / sinθ
Here n = 2 for second order maxima and d is the distance
= 2(600 × 10⁻⁶) / sin 39°
= 1200 × 10⁻⁶ / 0.6293
= 1.9 × 10⁻³ mm
N = 1/d
= 1 / 1.9 × 10⁻³
= 526
The grating has a line density of 526 lines per millimeter
The purpose of a rear view mirror in a car is to see behind the car, if there is any car coning or not.
