EM waves

G10_Unit 2: EM waves

Lesson Summary Part 2

How Electromagnetic Waves form

• Magnet is surrounded by magnetic field. It is same with charged particle, such as electron. An electric field surrounds a charged particle.

• It is form when electric charge accelerates by either speeding up, slowing down or changing direction.

Multiple Choice

1. Electromagnetic waves are produced by ___________.

• any disturbance

• currents

• vibrating charge

• voltage source

How EM waves form

• An electric charge is surrounded by an electric field. If the electric charge moves up and down, the field also moves up and down.

• A changing electric field produces a magnetic field and vice versa.

• The vibration of the charge starts a wave of vibrating electric and magnetic field that moves in all directions.

Multiple Choice

2. These are waves that are created as a result of vibrations between an electric field and magnetic field.

• electromagnetic spectrum

• electromagnetic wave

• microwave

• radio wave

Properties of EM wave

• Wavelength is the distance between one point to the nearest point of a wave.

• Frequency is the number of wavelength that pass by a point in a certain period of time, such as second.

Properties of EM wave

• As wavelength increase (longer), frequency decreases. As wavelength decreases (shorter), frequency increases.

• All EM waves carry energy. The higher the frequency, the higher the energy an EM wave carry.

Multiple Choice

3. The number of waves that pass a fixed point in unit time.

• Frequency

• Wavelength

• Energy

• Amplitude

Multiple Choice

4. It is the distance between two crests or two troughs in a transverse wave.

• Frequency

• Wavelength

• Energy

• Amplitude