The answer is D. Blackbody radiation. The piece of iron glows red because its temperature is around 1000 K, then yellow because its temperature is around 2800 K, and then white because its temperature is around 5500K. This shows that the spectrum of the radiation is determined by absolute temperature, as when the temperature of a blackbody radiator increases, the peak of the radiation curve moves to shorter wavelengths.
Answer:Thus, The magnetic field around a current-carrying wire is <u><em>directly</em></u> proportional to the current and <u><em>inversely</em></u> proportional to the distance from the wire. If the current triples while the distance doubles, the strength of the magnetic field increases by <u><em>one and half (1.5)</em></u> times.
Explanation:
Magnetic field around a long current carrying wire is given by

where B= magnetic field
permeability of free space
I= current in the long wire and
r= distance from the current carrying wire
Thus, The magnetic field around a current-carrying wire is <u><em>directly</em></u> proportional to the current and <u><em>inversely</em></u> proportional to the distance from the wire.
Now if I'=3I and r'=2r then magnetic field B' is given by

Thus If the current triples while the distance doubles, the strength of the magnetic field increases by <u><em>one and half (1.5)</em></u> times.
Answer:
Change in kinetic energy is ( 26CL³)/3
Explanation:
Given :
Net force applied, F(x) = Cx² ....(1)
Displacement of the particle from xi = L to xf = 3L.
The work-energy theorem states that change in kinetic energy of the particle is equal to the net amount of work is done to displace the particle.
That is,
ΔK = W = ∫F·dx
Substitute equation (1) in the above equation.
ΔK = ∫Cx²dx
The limit of integration from xi = L to xf = 3L, so

Substitute the values of xi and xf in the above equation.


Answer:
Two possible points
<em>x= 0.67 cm to the right of q1</em>
<em>x= 2 cm to the left of q1</em>
Explanation:
<u>Electrostatic Forces</u>
If two point charges q1 and q2 are at a distance d, there is an electrostatic force between them with magnitude

We need to place a charge q3 someplace between q1 and q2 so the net force on it is zero, thus the force from 1 to 3 (F13) equals to the force from 2 to 3 (F23). The charge q3 is assumed to be placed at a distance x to the right of q1, and (2 cm - x) to the left of q2. Let's compute both forces recalling that q1=1, q2=4q and q3=q.





Equating


Operating and simplifying

To solve for x, we must take square roots in boths sides of the equation. It's very important to recall the square root has two possible signs, because it will lead us to 2 possible answer to the problem.

Assuming the positive sign
:




Since x is positive, the charge q3 has zero net force between charges q1 and q2. Now, we set the square root as negative



The negative sign of x means q3 is located to the left of q1 (assumed in the origin).
This approach is called the dimensional analysis which involves only the units of measurement without their magnitudes. You simply have to do the operations by using variables. Cancel out like items that may appear both in the numerator and denominator side. The solution is as follows:
F = mv²/r = [kg][m/s]²/[m] = [kg][m²⁻¹][1/s²] = [kg·m/s²]