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Ipatiy [6.2K]
3 years ago
10

A 30w light bulb uses 600J of electrical energy in a certain period of time. In that time , it produces 450 J of light energy. T

he rest of the energy is wasted calculate the efficiency of the light bulb
Physics
1 answer:
Effectus [21]3 years ago
7 0
30*t=600
t=20 second

450=20*w
w=45/2
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You know that you sound better when you sing in the shower. This has to do with the amplification of frequencies that correspond
Elena L [17]

Answer:

Explanation:

For first overtone

Standing waves will be formed lengthwise and breadth-wise in the enclosures  having dimension of .75m  x 1.5 m

A ) For the formation of lowest two frequencies formed by standing waves along the breadth  , fundamental note and first overtone may be considered.  

For fundamental note ,  

the condition is  

wave length λ = 2L = 2 x 0.75 m  

λ = 1.5 m  

frequency n = v / λ

= 343 / 1.5  

= 229  Hz approx

For first overtone

λ = L = 0.75m

frequency n = v / λ

n = 343 / 0.75  

= 457 Hz approx

B)

For the formation of lowest two frequencies formed by standing waves along the length , fundamental note and first overtone may be considered.  

For fundamental note ,  

the condition is  

wave length λ = 2L = 2 x 1.5 m  

λ = 3 m  

frequency n = v / λ

= 343 / 3  

= 114 Hz approx

frequency n = v / λ

n = 343 / 1.5  

= 229 Hz approx

3 0
3 years ago
PLEASE HURRY What is "a section of a chromosome that typically contains the code for a particular protein, which determines a sp
castortr0y [4]

Answer:

It is a gene!!

Explanation:

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6 0
3 years ago
For what visible wavelengths of light do the reflected waves interfere constructively? The range of wavelength of visible light
Otrada [13]

Answer:

None of the wavelength is in the visible range

Explanation:

Constructive interference of the reflected waves for different wavelengths can be estimated using:

λ_{m} = 2nd/m

where m is 1,2,3, ...

Therefore:

m=1, λ_{1} = 750 nm

m=2, λ_{1} = 750/2 = 375 nm

The limits of eye's sensitivity is between 430 nm and 690 nm. Beyond this range, the eye's sensitivity drops to approximately 1% of its maximum value.

7 0
4 years ago
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Mrrafil [7]

Answer: 283.2\times 10^{-9}\ nC

Explanation:

Given

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Dielectric constant k=4

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Distance between capacitors d=5\ mm

Maximum charge that can be stored before dielectric breakdown is given by

\Rightarrow Q=CV\\\\\Rightarrow Q=\dfrac{k\epsilon_oA}{d}\cdot (Ed)\quad\quad [V=E\cdot d]\\\\\Rightarrow Q=k\epsilon_oAE\\\\\Rightarrow Q=4\times 8.85\times 10^{-12}\times 0.4\times 10^{-4}\times 2\times 10^8\\\\\Rightarrow Q=28.32\times 10^{-8}\\\\\Rightarrow Q=283.2\times 10^{-9}\ nC

4 0
3 years ago
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Amiraneli [1.4K]

Answer: soda

Explanation:

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3 years ago
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