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.
Complete Question
The complete question is shown on the first uploaded image
Answer:
The answer is a
Explanation:
The explanation is shown on the second uploaded image
By a positive test charge.
Answer:
b
Explanation:
the answer is b because if you do the math it equals to b
C.
The train first sped up, giving it a positive acceleration in the beginning. This eliminates D since that choice states that it begins with a negative acceleration. This also eliminates B since that choice states that the train only had a negation acceleration.
Next, the train slows down, giving it a negative acceleration. We’re looking for the answer choice that starts with a positive acceleration and ends with a negative one. This makes C the correct answer. Hope this helps!