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Arlecino [84]
4 years ago
8

A resistor with resistance R is connected to a battery that has emf 13.0 V and internal resistance r = 0.350 Ω . For what two va

lues of R will the power dissipated in the resistor be 81.0 W ?
Physics
1 answer:
makvit [3.9K]4 years ago
8 0

Answer:

R = 1,746 Ω

Explanation:

The power dissipated in the circuit is

   P = V I = V² / R

Let's find the current

   R = V² / P

Let's calculate

  R = 13²/81

   R = 2,096 Ω

This is total resistance

  R_total = R + r

   R = R_total - r

   R = 2,096 -0,350

   R = 1,746 Ω

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Normally, electromagnetic waves (light) are not polarized, so electromagnetic vibration occurs in all planes. But when we get these waves to vibrate in a single plane, we have polarized light.

This is possible because electromagnetic waves are transversal waves, this means the electric field oscillates in all normal directions to the direction of wave propagation.

In other words:

<em>Its oscillation occurs in the transversal direction to its propagation. </em>

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<h2>2.) Right answer: concave  </h2>

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The concave mirrors reflect the light making it converge in a focal point therefore they are used to focus the light. This occurs because the light is reflected with different angles, since the normal to the surface varies from one point to another of the mirror.

<h2>3.) Right answer: photoelectric effect </h2>

phenomenon that can be explained only by a particle model for light: photoelectric effect  

Light can be considered as a wave or as particles (photons), in this context the photoelectric effect can only be explained based on the corpuscular model (particles) of light.

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experiment that showed that diffraction effects could be attributed to light particles: Taylor's experiment  

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Mirrors fulfill the principle of reflection, which occurs when the light rays fall on a very flat reflecting surface are reflected so that the incident angle is equal to the reflected angle

<h2>6.) Right answer: mirage  </h2>

image of the sky seen on a hot road: mirage

A mirage is the product of an optical illusion due to the total reflection of the light when crossing layers of hot air of different density; this causes the perception of the inverted image of distant objects, as if they were reflected in the water.

<h2>7.) Right answer: virtual  </h2>

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Help please
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Answer:

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Explanation:

You are asked to select the correct answer

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the correct answer is D

2) when a body falls, the gravitational potential energy is transformed into kinetic energy and both are transformed into thermal energy

the correct answer is D

3) When the gravitational potential energy is maximum, the kinetic energy is minimum and when the kinetic energy is maximum, the gravitational energy is minimum.

Correct answer B

4) speed is defined by

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so the correct answer is B in the SI system

5) when we repeat a measurement several times, the random or statistical errors decrease, therefore the confidence of the measurement increases.

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