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9966 [12]
4 years ago
11

A 60-W light bulb radiates electromagnetic waves uniformly in all directions. At a distance of 1.0 m from the bulb, the light in

tensity is I0, the average energy density of the waves is u0, and the rms electric and magnetic field values are E0 and B0, respectively.
1. At 2.0 m from the bulb, what is the light intensity?

2. At 2.0 m from the bulb, what is the rms magnetic field value?

3. At 2.0 m from the bulb, what is the average energy density of the waves?
Physics
1 answer:
krek1111 [17]4 years ago
5 0
1. If we increase the distance to twice it's original value, the light intensity is reduced by one-fourth, the light intensity would be:
I0/4

2. rms magnetic field is inversely proportional to distance, so the new rms magnetic field would be:
B0/2

3. average energy density is inversely proportional to the square of the distance, so the new average energy density is:
E0/4
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The force applied to the spring is the weight of the object that compresses it, so it is equal to:
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3 years ago
An airplane is flying 340 km/hr at 12o east of north. the wind is blowing 40 km/hr at 34o south of east. what is the plane's act
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Define an x-y coordinate system such that
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The wind blows at 40 km/h in the direction 34° south of east. Its velocity vector is
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The plane's actual velocity is the vector sum of the two velocities. It is
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The magnitude of the actual velocity is
v = √(121.1615² + 306.0473²) = 329.158 km/h

The angle that the velocity makes north of east is
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3 years ago
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3 years ago
A juggler throws a bowling pin straight up with an initial speed of 8.20 m/s. How much time elapses until the bowling pin return
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Answer:

1.68 s

Explanation:

From newton's equation of motion,

a = (v-u)/t.................................. Equation 1

Making t the subject of the equation

t =(v-u)g............................. Equation 2

Where t = time taken for the bowling pin to reach the maximum height, v = final velocity bowling pin, u = initial velocity of the bowling pin, g = acceleration due to gravity.

Note: Taking upward to be negative and down ward to be positive,

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t = 0.84 s.

But,

T = 2t

Where T = time taken for the bowling pin to return to the juggler's hand.

T = 2(0.84)

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T = 1.68 s

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                                                       -----------------------------------------------------------------------

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Here e_{+1} ^{0} is the positron.

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Such temperature is very difficult to initiate the reaction on the earth surface. It should be carried out in an sustainable way also .Otherwise It will cause nuclear hazards.

6 0
3 years ago
Read 2 more answers
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