All categories

4 years ago

EXPLAIN HOW ENERGY IS TRANSMITTED THROUGH A MEDIUM

2 answers:

7 0

Energy can be transmitted through a medium in one of 3 ways:

Conduction - This occurs when particles of a substance collide with one another, transferring some of their energy to each other in the process. This generally occurs most rapidly in solids due to the close proximity and order of the particles, and most slowly in gases, due to the sparse nature of the particles.

Convection - This occurs when a fluid has a temperature gradient decreasing with increasing altitude. For example, when a pan of water is heated, the higher energy water molecules at the bottom have a lower density than the lower energy molecules at the top of the pan and travel upwards through the liquid, while their place is taken by the lower energy molecules. This phenomenon also occurs in gases (think hot air balloon).

Radiation - This does not involve the movement of particles whatsoever, instead the energy is being transferred in the form of electromagnetic radiation (such as light). This is how the Sun heats the earth, as there are very few particles in space, certainly not enough for conduction/convection. (Note: this does technically involve the movement of particle called photons that make up the radiation, but they are not treated as physical particles like molecules).

Hope this helps.

jek_recluse [69]4 years ago

5 0

I say it helped then because TrueType had room

You might be interested in

A television of mass 12 kg sits on a table. The coefficient of static friction between the table and the television is 0.83. Wha

Zinaida [17]

The normal reaction between the television and the table is
N = 12 × 9.8 m/s² = 117.6 Newtons

But the static coefficient of friction is μ = 0.83

When the television is about to slide on the table, the applied force should overcome the force due to static friction;
Thus; the applied force should be at least
F = μN
= 0.83 × 117.6 N
= 97.608 Newtons
Therefore; the minimum applied force will be 97.6 Newtons.

4 0

4 years ago

Read 2 more answers

Unpolarized light of intensity I=10 falls on two successive polarizer wheels with the angle between the polarizer wheels e-60°.

yan [13]

Answer:

$I=\frac{10}{4}$

Explanation:

A polarizer changes the orientation of the oscillations of a light wave.

I₀ = Intensity of unpolarized light = 10

θ = Angle given to the polarizer = 60°

Intensity of light

I = I₀cos²θ

⇒I = 10cos²60

$\\\Rightarrow I=10\times \frac{1}{2}\times \frac{1}{2}\\\Rightarrow I=\frac{10}{4}$

So, the after passing through the second polarizer is $\mathbf{\frac{10}{4}}$

5 0

3 years ago

When light of wavelength 240 nm falls on a potassium surface, electrons having a maximum kinetic energy of 2.93 eV are emitted.

olchik [2.2K]

A) We want to find the work function of the potassium. Apply this equation:

E = 1243/λ - Φ

E = energy of photoelectron, λ = incoming light wavelength, Φ = potassium work function

Given values:

E = 2.93eV, λ = 240nm

Plug in and solve for Φ:

2.93 = 1243/240 - Φ

Φ = 2.25eV

B) We want to find the threshold wavelength, i.e. find the wavelength such that the energy E of the photoelectrons is 0eV. Plug in E = 0eV and Φ = 2.25eV and solve for the threshold wavelength λ:

E = 1243/λ - Φ

0 = 1243/λ - Φ

0 = 1243/λ - 2.25

λ = 552nm

C) We want to find the frequency associated with the threshold wavelength. Apply this equation:

c = fλ

c = speed of light in a vacuum, f = frequency, λ = wavelength

Given values:

c = 3×10⁸m/s, λ = 5.52×10⁻⁷m

Plug in and solve for f:

3×10⁸ = f(5.52×10⁻⁷)

f = 5.43×10¹⁴Hz

7 0

3 years ago

Three uniform spheres of radius 2R, R, and 3R are placed in a line, in the order given, so their centers are lined up and the sp

kolezko [41]

Answer:

x = 2.33 R from the center of mass of the smallest sphere.

Explanation:

Due to the symmetry of the spheres, the center of mass of any of them, is located just in the center of the sphere.

If we align the centers of the spheres with the x-axis, the center of mass of any of them will have only coordinates on the x-axis, so the center of mass of the system will have coordinates on the x-axis only also.

By definition, the x-coordinate of the center of mass of a set of discrete masses m₁, m₂, m₃, can be calculated as follows:

$Xcm = \frac{m1*x1+m2*x2+m3*x3}{m1+m2+3}$

In this case, we need to get the coordinates of the center of mass of each sphere:

If we place the spheres in such a way that the center of the first sphere has the x-coordinate equal to its radius (so it is just touching the origin), we will have:

x₁ = 2*R

For the second sphere, the center will be located at a distance equal to the diameter of the first sphere plus its own radius, as follows:

x₂ = 4*R + R = 5*R

Finally, for the third sphere, the center will be located at a distance equal to the diameter of the first sphere, plus the diameter of the second sphere, plus its own radius, as follows:

x₃ = 4*R + 2*R + 3*R = 9*R

We can calculate the mass of each sphere (assuming that all are from the same material, with a constant density), as the product of the density and the volume:

m = ρ*V

For a sphere, the volume can be calculated as follows:

$\frac{4}{3} *\pi *(r)^{3}$

So, we can calculate the masses of the spheres, as follows:

m₁ = ρ* $\frac{4}{3} *\pi *(2r)^{3}$

m₂ = ρ* $\frac{4}{3} *\pi *(r)^{3}$

m₃ = ρ* $\frac{4}{3} *\pi *(3r)^{3}$

The total mass can be calculated as follows:

M= ρ* $\frac{4}{3} *\pi$ * (8*r³ + r³ + 27*r³) =ρ* $\frac{4}{3} *\pi$ * 36*r³

Replacing by the values, and simplifying common terms, we can calculate the x-coordinate of the center of mass of the system as follows:

$Xcm = \frac{m1*x1+m2*x2+m3*x3}{m1+m2+3}$

$Xcm = \frac{(8*R^{3} *2*R)+(R^{3}*(5*R))+27*R^{3}*(9*R))}{36*R^{3} }=\frac{264*R^{4} x}{36*R^{3}} = 7.33 R$

As the x-coordinate of the center fof mass of the entire system is located at 7.33*R from the origin, and the center of mass of the smallest sphere is located at 5*R from the origin, the center of mass of the system is located at a distance d:

d = 7.33*R - 5*R = 2.33 R

4 0

3 years ago

This is me 1/10 rate please

kodGreya [7K]

Answer:

10 your absolutely beautiful, don't let anyone else tell you otherwise.

Explanation:

7 0

3 years ago

Read 2 more answers