Podcast
Questions and Answers
Why are electromagnetic waves like ultraviolet rays, X-rays, and gamma rays harmful to living things?
Why are electromagnetic waves like ultraviolet rays, X-rays, and gamma rays harmful to living things?
Which of the following is a useful application of infrared radiation to humans?
Which of the following is a useful application of infrared radiation to humans?
Which of the following is TRUE about infrared radiation and UV radiation?
Which of the following is TRUE about infrared radiation and UV radiation?
The following are useful applications of Ultraviolet Radiation EXCEPT
The following are useful applications of Ultraviolet Radiation EXCEPT
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Which of the following refers to the number of oscillations or wave per unit time and is measured in Hertz (Hz)?
Which of the following refers to the number of oscillations or wave per unit time and is measured in Hertz (Hz)?
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What wave property can best explain the apparent bending of a pencil when it is dipped into a glass of water?
What wave property can best explain the apparent bending of a pencil when it is dipped into a glass of water?
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When the object is at the center of curvature, the image formed is
When the object is at the center of curvature, the image formed is
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A ray through the center of curvature is reflected at
A ray through the center of curvature is reflected at
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Which of the following uses total internal reflection?
Which of the following uses total internal reflection?
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What happens to a light ray as it passes from one medium to another medium?
What happens to a light ray as it passes from one medium to another medium?
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A wave with a shorter wavelength must have a higher frequency, and vice versa.
A wave with a shorter wavelength must have a higher frequency, and vice versa.
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Which of the following EM waves has the highest energy, greatest frequency, and shortest wavelength?
Which of the following EM waves has the highest energy, greatest frequency, and shortest wavelength?
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What kind of lens should a person with myopia use?
What kind of lens should a person with myopia use?
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What image is formed in a concave mirror when the object is at the focal point?
What image is formed in a concave mirror when the object is at the focal point?
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What is the angle at which a ray of light is reflected from a mirror when it falls on it at an angle of 20° with the surface?
What is the angle at which a ray of light is reflected from a mirror when it falls on it at an angle of 20° with the surface?
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What is a useful application of infrared radiation to humans?
What is a useful application of infrared radiation to humans?
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Why are electromagnetic waves like ultraviolet rays, X-rays, and gamma rays harmful to living things?
Why are electromagnetic waves like ultraviolet rays, X-rays, and gamma rays harmful to living things?
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Which statement is TRUE about infrared radiation and UV radiation?
Which statement is TRUE about infrared radiation and UV radiation?
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Which of the following is NOT a useful application of Ultraviolet Radiation?
Which of the following is NOT a useful application of Ultraviolet Radiation?
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What refers to the number of oscillations or wave per unit time and is measured in Hertz (Hz)?
What refers to the number of oscillations or wave per unit time and is measured in Hertz (Hz)?
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What is the term for the maximum displacement of a wave from its rest position?
What is the term for the maximum displacement of a wave from its rest position?
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Which of the following is a source of electromagnetic waves?
Which of the following is a source of electromagnetic waves?
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What kind of lens should a person with myopia use?
What kind of lens should a person with myopia use?
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What happens to a light ray as it passes from one medium to another medium?
What happens to a light ray as it passes from one medium to another medium?
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Which wave property can best explain the apparent bending of a pencil when it is dipped into a glass of water?
Which wave property can best explain the apparent bending of a pencil when it is dipped into a glass of water?
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When the object is between the focal point and mirror, the image formed is:
When the object is between the focal point and mirror, the image formed is:
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What image is formed in a concave mirror when the object is at the focal point?
What image is formed in a concave mirror when the object is at the focal point?
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Which of the following uses total internal reflection?
Which of the following uses total internal reflection?
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A dentist uses a mirror to enlarge the image of a tooth to have a better view of cavity formations. What type of mirror does the dentist most likely use?
A dentist uses a mirror to enlarge the image of a tooth to have a better view of cavity formations. What type of mirror does the dentist most likely use?
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Which of the following refers to the number of oscillations or waves per unit time and is measured in Hertz (Hz)?
Which of the following refers to the number of oscillations or waves per unit time and is measured in Hertz (Hz)?
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Study Notes
Electromagnetic Waves
- Electromagnetic waves like ultraviolet rays, X-rays, and gamma rays are harmful to living things due to their high energy and frequency, which can cause damage to cells and tissues.
- Infrared radiation has a useful application in heating and warming, such as in heating pads and night vision devices.
- Infrared radiation has a lower energy and frequency than UV radiation.
Light Waves
- Frequency refers to the number of oscillations or wave per unit time, measured in Hertz (Hz).
- Wavelength and frequency are inversely proportional: a shorter wavelength means a higher frequency, and vice versa.
- Gamma rays have the highest energy, greatest frequency, and shortest wavelength among electromagnetic waves.
Mirrors and Lenses
- A ray through the center of curvature is reflected at the same angle as the incident ray.
- When the object is at the center of curvature, the image formed is real and inverted.
- A concave mirror forms a real and inverted image when the object is at the focal point.
- A person with myopia should use a concave lens to correct their vision.
Reflection and Refraction
- The apparent bending of a pencil when dipped into a glass of water can be explained by the wave property of refraction.
- When a light ray passes from one medium to another, it changes direction due to refraction.
- Total internal reflection is used in fiber optic communication.
Applications of Electromagnetic Waves
- Ultraviolet radiation has useful applications in disinfection, water purification, and cancer treatment.
- Infrared radiation is used in heating pads, night vision devices, and remote controls.
- A dentist uses a concave mirror to enlarge the image of a tooth to have a better view of cavity formations.
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Description
Test your knowledge on electromagnetic waves with this multiple-choice summative test. The test covers topics such as the useful applications of infrared radiation to humans and the harmful effects of electromagnetic waves like ultraviolet rays, X-rays, and gamma rays.