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3 years ago

8

If a current flowing through a lightbulb is 0.75 ampere and the voltage difference across the lightbulb is 120 volts, how much r

esistance does the light bulb have

1 answer:

Brut [27]3 years ago

6 0

Answer: $160 \Omega$

Explanation:

According to Ohm's law:

$V=R.I$

Where:

$V=120 V$ is the voltage difference across the light bulb

$R$ is the resistance of the light bulb (the value we want to find)

$I=0.75 A$ is the electric current

Isolating $R$ :

$R=\frac{V}{I}$

$R=\frac{120 V}{0.75 A}$

Finally:

$R=160 \Omega$ This is the resistance of the light bulb

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The total charge on the helix is

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Therefore, charge on spring

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For more information on linear charge density, visit

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8 0

2 years ago

Olegator [25]

Answer:

v2^2 - v1^2 = 2 g s fundamental formula

v2 = v1 + 2 g = v1 + 19.8 increase in velocity in 2 sec

v1^2 + 39.6 v1 + 392 - v1^2 = 2 * 9.8 * 123.1 = 2412.76

v1 = (2412.76 - 392) / 39.6 = 51.03

v2 = 51.03 + 19.6 = 70.63

T = 70.63 / .8 = 7.207 sec time to fall height of tower

S = 1/2 g T^2 = 4.9 * 7.207^2 = 254.5 m

(Note v2^2 - v1^2 = 70.63^2 - 51.03^2 = 2385 m

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3 years ago

What is the intensity level of a sound with an intensity of 0.000127 W/m2?

irina1246 [14]

DB = 10 log (I/Io)
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4 years ago

Bryan Allen pedaled a human-powered aircraft across the English Channel from the cliffs of Dover to Cap Gris-Nez on June 12, 197

Leno4ka [110]

(a) 3.58 km 45° south of east

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and the direction is exactly opposite to that of Allen, so it is 45° north of west. Allen's velocity relative to the ground is

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So this must be the resultant of Allen's velocity relative to the air (v') and the air's speed ( $v_a$ ). Since these two vectors are in opposite direction, we have

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v' = 5.53 m/s

Then the displacement of Allen relative to the air will be given by

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and substituting,

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And the direction is the same as that of the velocity, therefore will be 90° south of east.

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4 years ago

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zysi [14]

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4 years ago