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.
The car's speed is 240km/4hr= 60km/hr.
There's not enough information given in the question to determine its velocity.
Answer: True
Explanation:
A photo detector that can respond to the entire rang of visible light can be design, it is true.
Photo detector is a device in an optical receiver which receives optical signals and convert it to electric signal. It is the key device position in front of the optical receiver.
Answer:
A scalar is a quantity that is fully described by a magnitude only. It is described by just a single number. Some examples of scalar quantities include speed, volume, mass, temperature, power, energy, and time.
Examples of scalar quantity are:
Distance.
Speed.
Mass.
Temperature.
Energy.
Work.
Volume.
Area.
Explanation:
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