Answer:
a) 9.72 mm
b) 4.86 mm
Explanation:
wave length of light λ is 580 nm = 580 \times 10⁻⁹ m
Width of slit d = 0.215\times 10⁻³ m
Distance of screen D = 1.8 m.
Width of one fringe = 
Putting the values we get fringe width
= 
=4.86 mm.
a) Width of central maxima = 2 times width of one fringe
= 2 times 4.86
=9.72 mm
b) width of each fringe except central fringe is same , no matter what the order is.Only brightness changes .
So width of either of the two first order bright fringe will be same and it will be
= 4.86 mm.
For an ideal transformer power loss is assumed to be zero
i.e. the power in primary coil due to input voltage must be equal to power in secondary coil due to output voltage
this can be written in form of equation

here we know that


![i_1 = 10 A{/tex]now we will use above equation[tex]140*3.5 = 10 * V_1](https://tex.z-dn.net/?f=i_1%20%3D%2010%20A%7B%2Ftex%5D%3C%2Fp%3E%3Cp%3Enow%20we%20will%20use%20above%20equation%3C%2Fp%3E%3Cp%3E%5Btex%5D140%2A3.5%20%3D%2010%20%2A%20V_1)

So primary coil voltage is 49 Volts
Answer:
Part a)
P = 13.93 kW
Part b)
R = 8357.6 Cents
Explanation:
Part A)
heat required to melt the aluminium is given by

here we have



Since this is the amount of aluminium per hour
so power required to melt is given by



Since the efficiency is 85% so actual power required will be

Part B)
Total energy consumed by the furnace for 30 hours



now the total cost of energy consumption is given as



High density
random words to fill up 20 character minimum for answering questions :P
Answer:
C
Explanation:
First find the electrical wattage
W = I^2 * R
R = 12 ohms
I = 2 amps
Wattage = 2^2 * 12
Wattage = 4* 12
Wattage = 48 watts.
Now you need to use the power formula
Work = Power * Time
Work = ?
Power = 48 watts
Time = 3 minutes = 3 * 60 = 180 seconds.
Work = 48 * 180
Work = 8640 J
That's C