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4 years ago

Energy can be described in many ways. From the list below, what is the best definition of energy?

Physics

2 answers:

Aneli [31]4 years ago

5 0

The correct answer is A :)

4vir4ik [10]4 years ago

3 0

Answer:

A. anything that brings about changes.

Explanation:

Energy is something which is able to bring changes. It is a quantitative property which is transferred to an object to bring changes in the form to work, heat etc. It works on the law of conservation and SI unit of energy is joule while other units are calorie, kilo calorie, BTU, erg. Some common forms of energy are:- kinetic energy, potential energy, chemical energy, elastic energy.

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Which of the following is most useful to determine how much energy is being used by a circuit in a given amount of time?

user100 [1]

Answer:

The answer is A.

Explanation:

5 0

3 years ago

An electron is in a vacuum near Earth's surface and located at y = 0 m on a vertical y axis. At what value of y should a group o

Bingel [31]

Answer:

the bunch of 23 electrons must be placed on y axis at coordinate y = - 24.35 m.

Explanation:

As we know that the gravitational force on electron at y = 0 is counter-balanced by the weight of the electron

So we have

$\frac{kq_1q_2}{r^2} = mg$

here we have

$q_1 = e$

$q_2 = 23 e$

$m = 9.11 \times 10^{-31} kg$

also we know that

$e = 1.6 \times 10^{-19} C$

so we will have

$\frac{(9\times 10^9)(1.6 \times 10^{-19})(23\times 1.6 \times 10^{-19})}{r^2} = (9.11 \times 10^{-31})(9.81)$

$\frac{5.3 \times 10^{-27}}{r^2} = 8.94 \times 10^{-30}$

$r = 24.35 m$

so the bunch of 23 electrons must be placed on y axis at coordinate y = - 24.35 m.

7 0

3 years ago

Three polarizing filters are stacked, with the polarizing axis ofthe second and third filters at angles of 22.2^\circ and 68.0^\

andreev551 [17]

Answer:

I₂ = 25.4 W

Explanation:

Polarization problems can be solved with the malus law

I = I₀ cos² θ

Let's apply this formula to find the intendant intensity (Gone)

Second and third polarizer, at an angle between them is

θ₂ = 68.0-22.2 = 45.8º

I = I₂ cos² θ₂

I₂ = I / cos₂ θ₂

I₂ = 75.5 / cos² 45.8

I₂ = 155.3 W

We repeat for First and second polarizer

I₂ = I₁ cos² θ₁

I₁ = I₂ / cos² θ₁

I₁ = 155.3 / cos² 22.2

I₁ = 181.2 W

Now we analyze the first polarizer with the incident light is not polarized only half of the light for the first polarized

I₁ = I₀ / 2

I₀ = 2 I₁

I₀ = 2 181.2

I₀ = 362.4 W

Now we remove the second polarizer the intensity that reaches the third polarizer is

I₁ = 181.2 W

The intensity at the exit is

I₂ = I₁ cos² θ₂

I₂ = 181.2 cos² 68.0

I₂ = 25.4 W

8 0

4 years ago

Is it an inward force or an outward force that is exerted on the clothes during the spin cycle of an automatic washing machine?

harkovskaia [24]

An outward force is exerted

7 0

3 years ago

Humans can see several thousand shades of color but have cone photoreceptors that are sensitive to only three (perhaps four) wav

kipiarov [429]

Answer:

B. Color perception is achieved by activation of various combinations between the tree cone types.

Explanation:

Human eye have only three photo receptor ( three wavelength) but they can see several thousands of shades of color because color perception is gained by combination of these three wave length cone types ( RED, BLUE AND GREEN) into various combinations. Our retina have two types of cell:- cone cells and cylindrical cells. Cone cells are responsible for the identification of color.

4 0

3 years ago