Which one of the following statements with regard to the ultraviolet light is not correct?
- A.It is an electromagnetic wave.
- B.It can travel through vacuum.
- C.It is a longitudinal wave.
- D.Its wavelength is shorter/smaller than that of visible light.
Correct answer
Explanation
The correct answer is C. Ultraviolet light is an electromagnetic wave, and all electromagnetic waves are transverse, not longitudinal. In an electromagnetic wave, the electric and magnetic fields vibrate at right angles to each other and to the direction in which the wave travels, which is the mark of a transverse wave. Such waves need no medium, so ultraviolet rays from the Sun cross the vacuum of space to reach the Earth, all at the speed of light. Ultraviolet lies just beyond the violet end of the visible spectrum, with wavelengths of about 10 to 400 nanometres, shorter than visible light at about 400 to 700 nanometres. Longitudinal waves, in which particles vibrate along the direction of travel, include sound waves in air. Option A is wrong to pick because ultraviolet truly is an electromagnetic wave. Option B is wrong to pick because electromagnetic waves travel through a vacuum. Option D is wrong to pick because ultraviolet does have a shorter wavelength than visible light. Exam tip: all electromagnetic waves are transverse and travel through vacuum; sound is longitudinal and needs a medium.
Practice Questions
View allThe instrument used for detecting the presence of electric current in a circuit is
- A.Refractometer
- B.Galvanometer
- C.Viscometer
- D.Diffractometer
Show answer
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Read the full explanation →Reverberation is a phenomenon associated with a
- A.multiple refraction of sound.
- B.multiple reflection of sound.
- C.single refraction of sound.
- D.single reflection of sound.
Show answer
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Read the full explanation →Which one of the following is NOT a basic property of electric charge ?
- A.Charges can be added
- B.Charge is conserved
- C.Charge on a body is always an integral multiple of an electron or a proton charge
- D.Charges can be created and destroyed in an isolated system
Show answer
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Read the full explanation →Which of the following organelles have their own DNA and ribosomes?
- A.Endoplasmic reticulum and Golgi bodies
- B.Mitochondria and Chloroplast
- C.Endoplasmic reticulum and cytoskeleton
- D.Cell wall and nucleolus
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These two organelles carry their own circular DNA and their own small (70S) ribosomes, so they can make some of their own proteins.
Read the full explanation →Which one of the following statements is NOT correct ?
- A.All proteins are enzymes
- B.Mostly enzymes are proteins
- C.All fats are energy rich compounds
- D.Glucose is a common carbohydrate
Show answer
This statement is false: enzymes are mostly proteins, but most proteins are not enzymes. Proteins do many jobs in the body.
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