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sergij07 [2.7K]

2 years ago

10

at what position an object be placed in front of a concave mirror of radius of curvature 40cm so that an erect image of magnific

ation of 3 be produced ?

1 answer:

Thepotemich [5.8K]2 years ago

8 0

C=40cm
f=C/2=40/2=20

m=3

$\\ \sf\longmapsto m=\dfrac{f}{f-u}$

$\\ \sf\longmapsto 3=\dfrac{20}{20-u}$

$\\ \sf\longmapsto 3(20-u)=20$

$\\ \sf\longmapsto 60-3u=20$

$\\ \sf\longmapsto 3u=40$

$\\ \sf\longmapsto u=13.3cm$

m=magnification
f is focal length
C is radius of curvature
u is object distance

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Answer:

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Let t be the time both you and your friend take to walk to the restaurant.

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$s_1 = v_1t = 1.6t$

Similarly the distance (m) from your friend building to the restaurant:

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Let b be the length (in m) of a block, the total distance of 5 blocks is 5b

$s_1 + s_2 = 5b$

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3 years ago

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Aleonysh [2.5K]

Answer:

a) <em>8.33 x 10^-6 Pa</em>

b) <em>8.23 x 10^-11 atm</em>

c) <em>1.67 x 10^-5 Pa</em>

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<em></em>

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speed of light $c$ <u> </u>= 3 x 10^8 m/s

a) we know that the pressure for for a totally absorbing surface is given as

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3 years ago

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Alborosie

Answer:

Explanation:

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