Answer:
Explanation:
Moving a magnet might cause a change in the magnetic field going through the solenoid. Whether or not it will change depends on the movement.
According to Faraday's law of induction a voltage is induced in a coil by a change in the magnetic flux. Magnetic flux is defined as the dot product of the magnetic field (a vector field) by the area enclosed by a loop of the coil.

The voltage is induced by the variation of the magnetic flux:

Where
ε: electromotive fore
N: number of turns in the coil
ΦB: magnetic flux
Moving the magnet faster would increase the rare of change of the magnetic flux, resulting in higher induced voltage.
Turning the magnet upside down would invert the direction of the magnetic field, reversing the voltage induced.
Answer:
The uniy which is accepted all over the world is called SI unit.
Explanation:
The system of measurement that is agreed by the international convention if scientists that is held in paris of France to adopt an international unit is called SI unit unit.
If you multiply m (the unit for wavelength) with 1s (the unit for frequency), you will get m/s, the unit for speed. Now multiply! 25 m/s is your final answer!
Answer:
a) 3-in. pipe
Explanation:
Given that
Fluid flow is in same amount in the same time it means that volume flow rate is same for the pipes
Volume flow rate
Q = A V
A=Area ,V=Velocity

If diameter d is more then the velocity will be less for same volume flow rate .We also Know that if pressure is more then the velocity will be less.
The second pipe 3 in diameter having more diameter then the velocity will be less but the pressure will be more.
That is why the 3 in diameter is having more pressure than 2 in diameter pipe.
Therefore the answer will be a.
a) 3-in diameter pipe
Answer:
Explanation:
We shall apply Stefan's formula
E = AσT⁴
When T = 300
I₁ = Aσ x 300⁴
When T = 400K
I₂ = Aσ x 400⁴
I₂ / I₁ = 400⁴ / 300⁴
= 256 / 81
= 3.16
I₂ = 3.16 I₁ .