Explanation

The induced electromotive force (emf) ($varepsilon$) in a moving conductor in a magnetic field can be calculated using the formula:

$$\epsilon =B\cdot L\cdot v$$

Where:

• $B$ is the magnetic field strength (in teslas),
• $L$ is the length of the conductor (in meters),
• $v$ is the velocity of the conductor (in meters per second).

Given:

• $B = 0.6 , text{T}$
• $L = 1 , text{m}$
• $v = 20 , text{m/s}$

Substituting the values into the formula:

$$\epsilon =0.6\text{T}\cdot 1\text{m}\cdot 20\text{m/s}=12\text{V}$$

Thus, the value of the induced emf is 12 V.

Explanation

Inside a solenoid, the magnetic field is:Uniform and directed along the axis of the solenoid.

 The field lines are parallel and evenly spaced, indicating a strong and consistent magnetic field inside the solenoid.

Explanation

The force $F$ acting on a charged particle moving in a magnetic field is given by the Lorentz force equation, which can be expressed as:

$$F = q(mathbf{v} times mathbf{B})$$

Where:

• $\mathrm{<font\; color="\#0000ff"><b>F\; is\; the\; force\; acting\; on\; the\; particle,</b></font>}$
• $q$ is the charge of the particle,
• $mathbf{v}$ is the velocity vector of the particle,
• $\mathbf{B}$ is the magnetic flux density (magnetic field strength) vector.

The cross product $\mathbf{v}\times \mathbf{B}$ indicates that the direction of the force is perpendicular to both the velocity and the magnetic field vectors. Thus, the correct expression for the force is $F=qv\times B$.

Explanation

When an electron moves perpendicular to a magnetic field, the electromagnetic force (also known as the Lorentz force) acting on the electron is given by the formula:

F=qvBsin(θ)

Where:

• $F$ is the force,
• $q$ is the charge of the electron,
• $v$ is the velocity of the electron,
• $B$ is the magnetic field strength,
• $$θtheta is the angle between the velocity vector and the magnetic field.

When the electron is moving perpendicular to the magnetic field, $theta = 90^circ$ and $sin(90^circ) = 1$

Therefore, the force becomes:

$$F=qvB$$

This means the force is at its maximum value since both the charge and the velocity contribute to the force. Thus, the statement that the force acting is maximum is correct.

Explanation

An electron volt (eV) is a unit of energy.

It is defined as the amount of kinetic energy gained or lost by a single electron when it is accelerated through an electric potential difference of one volt.

Specifically:

1eV=1.602×10 −19 Joules

Thus, the electron volt is a convenient unit for measuring small amounts of energy, particularly in the fields of atomic and particle physics.

Explanation

The maximum power transfer theorem states that maximum power is delivered to the load when the load resistance 𝑅𝐿 is equal to the source (or internal) resistance Rs of the power source.

Mathematically, this can be expressed as:

𝑅𝐿 =𝑅𝑠

When the load resistance matches the source resistance, the power transferred to the load is maximized.

Explanation

Explanation

For most metals, the temperature coefficient of resistance is positive, meaning that as the temperature increases, the resistance of the metal also increases.

This behavior occurs because, at higher temperatures, the metal atoms vibrate more, leading to more collisions with the electrons flowing through the material, which increases resistance.

Thus, the temperature coefficient of resistance for metals is positive.

Explanation

Explanation

For non-Ohmic materials, the current-voltage (I-V) relationship does not follow Ohm's law, which states that current is directly proportional to voltage (resulting in a linear I-V graph).

In non-Ohmic materials, the relationship between current and voltage is non-linear, and the I-V graph is typically curved.

Examples of non-Ohmic materials include diodes and transistors, where the resistance changes with voltage or current.