Answer:
Explanation:
Area of square loop = L²
Flux Φ = area x magnetic field
= L²B
Frequency = f
angular velocity ω = 2πf
a )
Let at time t = 0 , the magnetic field is making 90 degree with the face of the loop
flux through loop = L²B
After time t , coil will turn by angle ω t = 2πft
Flux through the loop = L²B cosω t
Φ (t) = L²B cosω t
= L²B cos2πft
b )
emf induced e
= - d/dt [Φ (t)]
= - d/dt [ L²B cosω t]
= L²B ω sinω t
= L²B 2πf sin2πft
c )
current = e / R
(L²B ω/ R ) sinω t
Power delivered
P(t) = VI ,
VOLT X CURRENT
= AB ω sinω t X ( AB ω/ R ) sinω t
= L⁴B² 4π²f²/R sin²2πft
e )
torque = MB sinω t
τ(t) = i(L²B ) sinω t
= (L²B ω/ R ) sinω t x (L²B ) sinω t
= (L²B )²ω/ R sin²ω t
= (L²B )² 2πf/ R sin²2πft
We need optics to help aid people who have short or long sightedness.
we need optics to be able to watch TV
we need optics to be able to use the internet at high speeds
there are a tonne of reasons why we need optics.
Sunspots are spot like structure on the surface of sun, they are created due to geomagnetic flux which inhibits the convection of heat waves thus reducing the temperature of spot with some factor