Mechanical Energy = PE + KE
PE: mgh = 200 x 9.8 x 18 = 35280
PE: 35280 Joules
KE: 1/2mv^2 = 1/2 x 200 x 16^2 = 25600
KE: 25600 Joules
ME: 35280 + 25600
ME: 60,880J
When person is observing destructive interference at 0.20 m distance from the equidistant position then we can say that path difference must be equal to half of the wavelength
now we will have

now we know that
y = 0.20 m
d = 2.4 m
L = 10 m
now here we have


now frequency of wave is given as


<h3><u>Given :- </u></h3>
- Length of the rectangular wire, L=0.3 m
- Width of the rectangular wire, b=0.2m
- Magnetic field strength, B=0.8 T
- Velocity of the loop, v =12 m/s
- Induced Current, I = 3 A

(I) Emf developed,E in the loop is given as:



I = E/R
R = E/I
where
- R = resistance
- E = Induced EMF
- I = Current


(ii) The direction of current induced is from P to Q which is given by B × V vector . It may also be explained by Lenz law. Since magnetic field is from S to N . The fingers of the right hand are placed around the wire so that the curling of fingers will show the direction of the magnetic field produced by the wire then the thumb points in the direction of current flow which is from P to Q.
<span>Amorphous silica has a density of about 2.2 g/cm3, whereas the density of crystalline quartz is 2.65 g/cm3
</span><span>The difference in densities is
The atoms in amorphous silica do not pack as efficiently in three dimensions as compared to the atoms in quartz.
hope it helps</span>