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kolbaska11 [484]

2 years ago

7

Consider three identical electric bulbs of power P. Two of bulbs are connected in series and the third one is connected in paral

lel to the first two. The total power dissipated in this circuit is: a. 2P/3 b. 3Pc. 2Pd. 3P/2e. P

1 answer:

Tamiku [17]2 years ago

6 0

Answer: 3P/2

Explanation: Let the resistance of the bulbs be R.

now lets consider a Voltage V is supplied to the parallel circuit such that

$P=VI=V^2/R$

V=IR

both single bulb( bulb 3) and the two bulbs ( bulb 1 and bulb 2) are provided the same Voltage

( as the voltage remains same in parallel circuit)

we can calculate the Current across both circuits

At Bulb 3

Current 1=V/R

Power1=Voltage * Current1

Power1=V*V/R

Power1=P

At Bulb 1 and Bulb 2

Total Resistance= R+R=2R

$Current2=\frac{V}{2R}$

Power2=Voltage * Current2

$Power2=V*\frac{V}{2R} \\Power2=\frac{V^2}{2R} \\Power2=P/2$

$TotalPower=Power1+Power2\\TotalPower=P+P/2\\TotalPower=\frac{3P}{2}$

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An ancient club is found that contains 100 g of pure carbon and has an activity of 6.5 decays per second. Determine its age assu

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$N_{c_{14}}=1.30\times10^{-12}N_{12_{c}}$

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$R=100\times15.0650=1507\ decay/min$

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$(\dfrac{1}{2})^{n}=\dfrac{390}{1507}$

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Using formula of age

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$t=11103.6 =11104\ years$

Hence, The age of living tree is 11104 years.

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