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spin [16.1K]
3 years ago
14

A lightbulb has an effciency of 8.2%. How much light energy (not heat energy) is generated by the bulb every second if the buld

has pwer of 21w?
Physics
1 answer:
telo118 [61]3 years ago
8 0
It really depends on what the bulb is being used for, since efficiency means how much of the output is USEFUL.
If the bulb is being used for light in a dark room, then it produces (8.2% x 21W) = 1.72 joules per second of light energy.
If the bulb is being used to keep a hamster cage or a fish tank warm, then the 8.2% is the useful part, and the light is the other (91.8% x 21W) = 19.28 joules per second.
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Answer:

A) equal to the battery's terminal voltage.

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When the capacitor is fully charged after long hours of charging , its  potential becomes equal to the emf of the battery and its polarity is opposite to that of battery . Hence net emf becomes equal . The capacitor itself becomes a battery which is connected in the circuit with opposite polarity . This results in the net emf and  current becoming zero . There is no charging current when the capacitor is fully charged .

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Glottis is the organ that is considered to be the opening to the windpipe. It consists of vocal chords wherein voice modulation usually takes place. The production of the sounds of the organ can be mainly attributed to the "buzzing" vibration inside the vocal chords wherein they vibrate.
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2 years ago
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What is the frequency of a wave whose wavelength is 0.7m and whose velocity is 120m/s?
ANEK [815]

Answer:

f=171.43Hz

Explanation:

Wave frequency is the number of waves that pass a fixed point in a given amount of time.

The frequency formula is: f=v÷λ, where <em>v</em> is the velocity and <em>λ</em> is the wavelength.

Then replacing with the data of the problem,

f=\frac{120\frac{m}{s} }{0.7m}

f=171.43\frac{1}{s}

f=171.43 Hz (because \frac{1}{s} = Hz, 1 hertz equals 1 wave passing a fixed point in 1 second).

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When a conductive wire is used to build a loop, a solenoid is formed.

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To learn more about the solenoid refer to the link ;

brainly.com/question/16015159

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