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Setler79 [48]
3 years ago
11

calculate minimum number of incident photons per area and of the minimum dose needed to visualize an object of 1 mm squared usin

g x rays of energy 50 keV. ( thickness 10^-3)(contrast 1%)
Physics
1 answer:
Lynna [10]3 years ago
3 0

Answer:

minimum number of photon is 4.05 × 10^{7}

Explanation:

given data

energy = 50 keV = 50 × 10^{3} eV =  50 × 10^{3} × 1.602× 10^{-19}  J

thickness = 10^-3

contrast = 1%

to find out

number of incident photons

solution

we know here equation that is

E  = n  × h  × ν   .......................1

put here all these value

50 × 10^{3} = n × 6.6× 10^{-34} × c/ 1× 10^{-3}

50 × 10^{3} × 1.602× 10^{-19}  = n × 6.6× 10^{-34} ×( 3 × 10^{8} / 1× 10^{-3})

solve it and find n

n = 4.05 × 10^{7}

so here minimum number of photon is 4.05 × 10^{7}

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Answer:

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Explanation:

The connection arrangement of the headlight and the engine starter = Parallel to the battery

The voltage of the battery, V = 12.0 V

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The power at which the kick starter operates in parallel, P_{kick \ starter} = 2.40 kW

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P = V²/R

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V = The voltage = 12 V (The voltage is the same in parallel circuit)

For the headlight, we have;

R₁ = V²/P_{headlight}  = 12²/38 = 72/19

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For the kick starter, we have;

R₂ = V²/P_{kick \ starter} = 12²/2.4 = 60

R₂ = 60 Ω

When the headlight and kick starter are rewired to be in series, we have;

Total resistance, R = R₁ + R₂

Therefore;

R = ((72/19) + 60) Ω = (1212/19) Ω

The current flowing, I = V/R

∴ I = 12 V/(1212/19) Ω = (19/101) A

We note that power, P = I²R

In the series connection, we have;

P_{headlight} = I² × R₁

∴ P_{headlight} = ((19/101) A)² × 72/19 Ω = 1368/10201 W ≈ 0.134 W

The power at which the headlight operates in series, P_{headlight, S} ≈ 0.134 W

P_{kick \ starter} = ((19/101) A)² × 60 Ω = 21660/10201 W ≈ 2.123 W

The power at which the kick starter operates in series, P_{kick \ starter, S} ≈ 2.123 W

The total power they will consume, P_{Total} = P_{headlight, S} + P_{kick \ starter, S}

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3 years ago
You travel 20.0 mph for 0.500 hour, 40.0 mph for 1.00 hour, 30.0 mph for 0.500 hour, and 50.0 mph for 2.00 hours. What is the av
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The average speed (v) can be expressed as:
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T is total time: T = t1 + t2 + t3 + t4

Now let's calculate distances using the formula: d = v * t:
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Thus, the average speed is:
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Answer:

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Explanation:

Hello!

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COP=\frac{T1}{T2-T1}

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