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2 years ago

How can resistance be useful and where can they be useful?

1 answer:

3 0

-- Resistance can be useful among the population of a repressive government.
Although it can be dangerous for those who resist, it can also exert pressure
against the regime to alter its repressive practices.

-- Resistance can also be useful in electronic circuits. "Lumped" components with
known numerical values of resistance are used to divide voltage, limit current, and
dissipate controlled amounts of electrical energy.

You might be interested in

A flying saucer lifts the Physical Science building 10,000 ft into the air before discovering it is useless and discards the rem

scZoUnD [109]

Answer:

500000000 lbft/s

Explanation:

F = Force or weight = 1000000 lbf

s = Displacement = 10000 ft

t = Time taken = 20 seconds

Work done is given by

$W=Fs\\\Rightarrow W=1000000\times 10000\\\Rightarrow W=10000000000\ lb-ft$

Power is given by

$P=\dfrac{W}{t}\\\Rightarrow P=\dfrac{10000000000}{20}\\\Rightarrow P=500000000\ lbft/s$

One Saucer power is 500000000 lbft/s

7 0

3 years ago

What causes the inner core to be solid?

natima [27]

Your answer will be (B) - intense pressure.

4 0

2 years ago

Why is it not necessary for radio telescope surfaces to be as smooth as a mirror?

Law Incorporation [45]

It doesn't on account of radio waves are longer than optical waves. Radio waves are a sort of electromagnetic radiation with wavelengths in the electromagnetic range longer than infrared light. These long waves are in the radio locale of the electromagnetic range.

8 0

3 years ago

A ruler of length 0.30m is pivoted at its centre. Equal and opposite forces of magnitude 2.0N are applied to the ends of the rul

kow [346]

Answer:

0.3858 Nm

Explanation:

The torque of the couple is the dot product of the force vector and the couple vector from 1 end of the ruler to the center. This equals to the product of their magnitude times the cosine() of the angle made by their direction:

$T = \vec{F} \cdot \vec{s} = Fscos(50^0) = 2 * 0.3 * 0.643 = 0.3858 Nm$

6 0

3 years ago

The expansion of the universe has also been compared to the inflation of a balloon. Suppose that before you inflate the balloon,

Alona [7]

Answer:

That the universe (the balloon for this case) is expanding and that is the reason why the galaxies (the dots) appear to move away one from another.

Explanation:

By means of looking at the spectra of galaxies, it can confirm that they are moving away in an accelerated motion.

Spectral lines will be shifted to the blue part of the spectrum if the source of the observed light is moving toward the observer, or to the red part of the spectrum when it is moving away from the observer (that is known as the Doppler effect). The source in this particular case is represented for each of the galaxies.

Hence, the redshift represents this shift of the spectral lines to red part in the spectrum of a galaxy or any object which is moving away. That is a direct confirmation of how the universe is in an expanding accelerated motion.

The redshift can be define in analitic way by trought the doppler velocity:

$v = c\frac{\Delta \lambda}{\lambda_{0}}$ (1)

Where $\Delta \lambda$ is the wavelength shift, $\lambda_{0}$ is the wavelength at rest, v is the velocity of the source and c is the speed of light.

$v = c(\frac{\lambda_{measured}-\lambda_{0}}{\lambda_{0}})$

$\frac{v}{c} = \frac{\lambda_{measured}-\lambda_{0}}{\lambda_{0}}$

$z = \frac{\lambda_{measured}-\lambda_{0}}{\lambda_{0}}$ (2)

Where z is the redshift.

The ballon example, once that it is inflating, represents how is the universe which it is expanding and that is the reason why the galaxies (the dots) appear to move away one from another.

7 0

3 years ago