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3 years ago

A lamp that uses 100.0 watts of power requires a voltage of 210.0 volts. What is the resistance of the lamp?

Physics

2 answers:

bixtya [17]3 years ago

8 0

Answer:

R = 441 ohms

Explanation :

It is given that,

Power of the lamp, P = 100 watts

Voltage, V = 210 volts

The power of an electrical appliance can be written as :

$P=\dfrac{V^2}{R}$

$R=\dfrac{V^2}{P}$

$R=\dfrac{(210\ V)^2}{100\ W}$

R = 441 ohms

So, the resistance of the lamp is 441 ohms

Hence, this is the required solution.

alexandr402 [8]3 years ago

6 0

Resistance = Voltage/Current
Wattage = Voltage * Current

<span> <span> </span> </span> That means the current drawn by the lamp is equal to 100 watts divided by 210 volts.

Resistance = $\frac{210}{ \frac{100}{210} }$

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Answer:

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D: screen distance

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d) the wavelength of a laser in which its first order fringe coincides with the third one of the CuAr laser is:

$y=\frac{(3)(633*10^{-9}m)(0.063m)}{0.02*10^{-3}m}=5.98*10^{-3}m\approx0.59cm\\\\\lambda'=\frac{dy}{mD}=\frac{(0.02*10^{-3}m)(0.59*10^{-2}m)}{(1)(0.063m)}=1.87*10^{-6}m$

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Answer:

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slamgirl [31]

Answer:

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