The temperature inside the copper rod varies linearly with the distance from the hot end of the rod. This means that we can find the temperature at 23 cm (let's call it 'point A') from the cool end by solving a linear proportion.
The temperature difference between the two ends of the rod is

and this corresponds to a length of 81 cm. Therefore, we can write:

from which we find

This is not the final answer actually; this is the temperature difference between the cool end and point A. So, the temperature at point A is
Answer:
It can be seen from the operation of pin-hole camera, formation of shadows and eclipse.
Explanation:
The phenomenon of light traveling in a straight line is known as rectilinear propagation of light.
One this evidence can be seen from the operation of pin-hole camera, which depends on rectilinear propagation of light
Also two natural effects that result from the rectilinear propagation of light are the formation of Shadows and Eclipse.
Answer: What is this supposed to be converted into?
Explanation:
Answer:
The farther star will appear 4 times fainter than the star that is near to the observer.
Explanation:
Since it is given that the luminosity of the 2 stars is same thus they radiate the same energy per unit time
Consider a spherical wave front of energy 'E' that leaves both the stars (Both radiate 'E' as they have same luminosity)
This Energy is spread over the whole surface area of sphere Thus when the wave front is at a distance 'r' the energy per unit surface area is given by

For the star that is twice away from the earth the distance is '2r' thus we will receive an energy given by
Hence we sense it as 4 times fainter than the nearer star.