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solmaris [256]
3 years ago
8

A convex lens with focal length 9 cm forms an image of an object placed 21 cm to the left of the lens. what is the distance to t

he image formed?
Physics
1 answer:
bixtya [17]3 years ago
8 0

Answer:

15.75 cm

Explanation:

focal length of convex lens, f = + 9 cm

position of object, u = - 21 cm

Let the distance of image is v.

Use lens equation

1 / f = 1 / v - 1 / u

1 / 9 = 1 / v + 1 / 21

1 / v = 1 / 9 - 1 / 21 = (21 - 9) / (21 x 9)

1 / v = 12 / 189

v = 15.75 cm

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\large{\underline{\underline{\pmb{\frak {\color {red}{Question:}}}}}}

\sf \red{When \: baking \: soda \: is \: mixed \: with \: lemon \: juice, \: bubbles \: are \: formed \: with \: the \: evolution \: of \: a \: gas.}

\large{\underline{\underline{\pmb{\frak {\color {blue}{Answer:}}}}}}

When baking soda is mixed with lemon juice, bubbles are formed with the evolution of a gas. The gas is formed in the reaction is Carbon dioxide. CO_{2} is formed.

The change which happened in this reaction is a chemical change.

\boxed{ \frak \green{Explanation}}

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\boxed{ \frak \red{Brainlysamurai}}

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A LED light source contains a 0.5-Watts GaAs (Eg =1.43 eV) LED. Assuming that 0.12% of the electric energy is converted to emiss
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Answer:

Explanation:

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Eg = 1.43 eV .

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energy of one photon = 1.43 eV

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c )

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