QUARTER 2 REVIEWER

Who contributed to developing equations that show the relationship between electricity and magnetism?

• Andre Marie Ampere

• Isaac Newton

• James Clerk Maxwell

• Michael Faraday

Heinrich Hertz is known for his work with radio waves. How did his discoveries influence modern communication technology? 

• invented the first radio receiver.

• created the first FM radio station.

• developed the first television broadcasting system. 

• proved the existence of electromagnetic waves, paving the way for wireless communication. 

In an electromagnetic wave, how are the electric field, magnetic field, and direction of propagation oriented with respect to one another?

• form a circular pattern.

• oscillates in a linear fashion.

• perpendicular to each other.

• all aligned in the same direction.

Radio waves are part of the electromagnetic waves. Electromagnetic waves are created by accelerating charges; moving charges back and forth will produce oscillating electric and magnetic fields, and this travel at the speed of light. Based on the diagram, which describe radio waves?

• Longitudinal waves in which the displacement of the medium is in the same direction as, or the opposite direction to, the direction of travel of the wave.

• Mechanical waves in which propagate through a material medium (solid, liquid, or gas) at a wave speed which depends on the elastic and inertial properties of that medium.

• Transverse waves that are moving waves consist of oscillations occurring perpendicular (or right angled) to the direction of energy transfer.

• Standing waves that are produced whenever two waves of identical frequency interfere with one another while travelling opposite directions along the same medium.

Which of the relationships will describe the wavelength, frequency, and energy in the electromagnetic spectrum?

• Wavelength is directly proportional to frequency and energy.

• Wavelength is inversely proportional to frequency and directly proportional to energy.

• Frequency is directly proportional to energy and inversely proportional to wavelength.

• Frequency is directly proportional to wavelength and inversely proportional to energy.

Which of the following description/s is/are NOT TRUE about the infrared radiation as shown in the illustration? Its energy is _____.

I. Lower than the visible light you see.

II. Greater than the radio wave.

III. The same with the gamma ray.

IV. Almost close to the energy of the X-ray.

• I only

• II only

• I and II

• III and IV

Mr. Pedro asked his students to give an example of the sources that are arranged in a way that will pose an increasing risk to humans when exposed to the different sources of electromagnetic radiation at the same time duration and distance. Jean raises her hand and gives an answer to Sir Pedro. Observe the class conversation below:

Jean: “mobile AM/FM --> WiFi --> sunlight --> radioactive source”

Sir Pedro: “Very Good. Can you explain to your classmates the reason for your answer?

Which could be Jean’s possible answer to Sir Pedro’s follow-up questions?

• Energy decreases, frequency remains the same.

• Energy increases, frequency remains constant.

• Frequency increases, energy decreases.

• Frequency increases so as the energy.

An FM radio station broadcasts its signal at a frequency of 107.5 x 10^6 Hz using powerful transmitters. Calculate the wavelength of the radio wave to determine the signal reception at residential locations.

• 0.92 m

• 1.40 m

• 2.79 m

• 3.00 m

Violet light has a wavelength of 2.50 x 10^-7 m. Solve for the frequency?

• 1.20 x 10^15 Hz

• 2.40x10^15 Hz

• 3.00x10^14 Hz

• 6.00x10^12 Hz

During a live TV news report, a small satellite dish is used to send video signals to the broadcast station. What is being transmitted through the air?

• Light waves

• Microwaves

• Radio waves

• Sound waves