Electromagnetic Induction Lecture Notes

These flashcards cover key concepts of electromagnetic induction based on lecture notes.

What typically causes water hammering in plumbing systems?

Abruptly turning on or off water taps causing hydraulic shock.

Does the induced electric field in electromagnetic induction come from a battery?

No, the induced electric field is not due to a battery.

What observation is made when a magnet moves towards a loop of wire?

The ammeter deflects in one direction.

What happens to the ammeter when the magnet is stationary near the loop?

The ammeter shows no deflection.

What is required for an induced current to be produced?

A changing magnetic field.

According to Faraday's law, what is directly proportional to the induced e.m.f.?

The rate of change of magnetic flux.

What phenomenon does Lenz's law explain regarding induced current?

The induced current opposes the change in magnetic flux.

When is the induced current said to exist?

Only while the magnetic field is changing.

What defines the magnetic flux through a loop?

FB = BA cos θ, where θ is the angle between the magnetic field and the area normal.

What's the significance of the angle θ in magnetic flux?

Maximum flux occurs when θ = 0°, or when the magnetic field is perpendicular to the loop.

What is motional e.m.f.?

The e.m.f. induced in a conductor moving through a magnetic field.

How does the direction of induced current change with motion direction?

The polarity of the potential difference reverses if the direction of motion is reversed.

What is the effect of resistance in the circuit regarding induced current?

Induced current can flow only if the circuit is connected, with total resistance R.

What is one practical application of induced e.m.f. discussed in the lecture?

Induction stoves use eddy currents to heat cooking pots.

How does changing magnetic flux relate to the induced electric field?

A changing magnetic flux generates an electric field even in a conductor's absence.

Area of a rectangle

The area can be calculated using the formula: A = l \times w where $l$ is the length and $w$ is the width.

Circumference of a circle

The circumference can be calculated using the formula: C = 2\pi r where $r$ is the radius.

Pythagorean theorem

In a right triangle, the relationship between the lengths of the sides can be expressed as: a^2 + b^2 = c^2 where $c$ is the hypotenuse.

Quadratic formula

The solutions for a quadratic equation ax^2 + bx + c = 0 can be found using: x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}.

Slope of a line

The slope (m) of a line can be calculated with the formula: m = \frac{y2 - y1}{x2 - x1} for two points $(x1, y1)$ and $(x2, y2)$.