V = f x wavelength = 20000Hz x 0.075m = 1500 but V = $\frac{d}{t}$ = $\frac{2d}{3}$ (echo)$\rightarrow$ 2d = 4500 $\rightarrow$ d = 2250 m
johnmulu answered the question on February 11, 2017 at 08:44
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The wavelength of a radio wave is 1 km. Determine its frequency.
(Solved)
The wavelength of a radio wave is 1 km. Determine its frequency.
(Take the speed of light as 3.0 X 108ms-1)
Date posted:
February 11, 2017
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Answers (1)
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(Solved)
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Date posted:
February 11, 2017
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Answers (1)
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(Solved)
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(Speed of sound in air = 330m/s)
Date posted:
February 11, 2017
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Answers (1)
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(Solved)
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Date posted:
February 11, 2017
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Answers (1)
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(Solved)
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Date posted:
February 11, 2017
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Answers (1)
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(Solved)
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Date posted:
February 11, 2017
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Answers (1)
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(Solved)
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Date posted:
February 11, 2017
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(Solved)
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Date posted:
February 11, 2017
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Answers (1)
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(Solved)
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Date posted:
February 11, 2017
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Answers (1)
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(Solved)
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Date posted:
February 11, 2017
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Answers (1)
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An object of weight 20 N attached at the end of a spring causes an extension of 0.5 cm on the spring
(Solved)
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Date posted:
February 11, 2017
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Answers (1)
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(Solved)
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Date posted:
February 11, 2017
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(Solved)
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Date posted:
February 11, 2017
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Answers (1)
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(Solved)
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Date posted:
February 11, 2017
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(Solved)
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Date posted:
February 11, 2017
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Answers (1)
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(Solved)
State two ways in which the strength of an electromagnet can be increased.
Date posted:
February 11, 2017
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Answers (1)
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(Solved)
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Date posted:
February 11, 2017
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Answers (1)
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(Solved)
State two ways of increasing the force on the coil.
Date posted:
February 11, 2017
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Answers (1)
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(Solved)
Give reason why the core of the electromagnet of an electric bell is made of soft iron and not steel.
Date posted:
February 11, 2017
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Answers (1)
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State two factors that affect the strength of an electromagnet
(Solved)
State two factors that affect the strength of an electromagnet.
Date posted:
February 11, 2017
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Answers (1)