c] Electrons
Electron gets transferred
The electron's path in the magnetic field is a straight line when viewed from above.
In fact, the electron initially moves upward, while the magnetic field is directed horizontally. The electron experiences a force due to the magnetic field (the Lorentz force), whose direction is given by the right-hand rule:
- index finger --> initial direction of the electron (upward)
- middle finger --> direction of the magnetic field (horizontally, away from the observer)
- opposite direction to the thumb* --> direction of the force (horizontally, but perpendicular to the magnetic field, to the right)
This means that the Lorentz force makes the electron moving perpendicular to the magnetic field in the horizontal plane, and since the direction of the field is not changing, this force does not change its direction, so the electron moves in the same direction of the force in the horizontal plane (to the right), therefore following a straight line.
* the direction should be reversed because the charge is negative.
Answer:
aluminium > copper > steel (amount which get sag)
Explanation:
<u>Theory</u>
Linear expansivity (α) : The increase in length, per unit length per degree rise in temperature.
Therefore, α = Δl/Lθ
Δl = increase in length ( amount of sag in this case )
L = length of wire
θ = temperature change
We get, Δl = Lαθ
From that we get, amount of sag ∝ Linear expansivity (α)
Initial length of all three wires are the same.
The temperature change they subject also the same.
So the factor that changes the amount of sag is the coefficient of linear expansivity.
