## If ideal things like ideal gas or ideal machine dont exist, then why do we define such things and compare usual things to ideal ones?

Brijesh Kumar You are right. They should be called “simple” things. In reality, they are simplifications of real world systems. So, we should call: “simple gas” and “simple machine”. We use those to make our analysis easier. They are good approximations or starting points of real world systems. So, to call them an “ideal gas” … Read more

## If ideal things like ideal gas or ideal machine dont exist, then why do we define such things and compare usual things to ideal ones?

Brijesh Kumar You are right. They should be called “simple” things. In reality, they are simplifications of real world systems. So, we should call: “simple gas” and “simple machine”. We use those to make our analysis easier. They are good approximations or starting points of real world systems. So, to call them an “ideal gas” … Read more

## Does the conductance of a semiconducter change when the Fermi level $E_F$ stays the same, but the distance to the valence band increases?

Brijesh Kumar Conductance depends on the size of the material, so let us talk about conductivity which is independent of physical size. conductivity = $ne\mu_n+pe\mu_p$ Now, to solve this question, let us make some assumption: The density of states is the same in both materials (Nc, Nv) The mobility for both electrons and holes is … Read more

## Does the conductance of a semiconducter change when the Fermi level $E_F$ stays the same, but the distance to the valence band increases?

Brijesh Kumar Conductance depends on the size of the material, so let us talk about conductivity which is independent of physical size. conductivity = $ne\mu_n+pe\mu_p$ Now, to solve this question, let us make some assumption: The density of states is the same in both materials (Nc, Nv) The mobility for both electrons and holes is … Read more

## What smell will you never forget?

Brijesh Kumar Decomposing dead bodies In the 90’s, my uncle was going through medical school. There was an exhibition of human anatomy in his college. We all were very excited to go to see the various body parts in a human body. But, once we reached there, it was pure horror. There were cut open … Read more

## What smell will you never forget?

Brijesh Kumar Decomposing dead bodies In the 90’s, my uncle was going through medical school. There was an exhibition of human anatomy in his college. We all were very excited to go to see the various body parts in a human body. But, once we reached there, it was pure horror. There were cut open … Read more

## Why do we need a soundcard?

Brijesh Kumar Humans can hear analog sounds, we can’t hear digital sounds. Well, we can. Digital sounds, if they were directly converted would be very jarring to hear. You will have beeps corresponding to 1’s and periods of silence corresponding to 0’s. Digital signals consist of only 0’s and 1’s. But, computers can only deal … Read more

## Why do we need a soundcard?

Brijesh Kumar Humans can hear analog sounds, we can’t hear digital sounds. Well, we can. Digital sounds, if they were directly converted would be very jarring to hear. You will have beeps corresponding to 1’s and periods of silence corresponding to 0’s. Digital signals consist of only 0’s and 1’s. But, computers can only deal … Read more

## Are people in the US less judgmental than Indians?

Brijesh Kumar No. They just don’t express their judgments, because they know that others will judge them too and express their opinions. It is an unspoken rule: I don’t speak about bad things that you do and you don’t speak about bad things I do. Moreover, the standards expected from humans are consistently going down. … Read more

## Are people in the US less judgmental than Indians?

Brijesh Kumar No. They just don’t express their judgments, because they know that others will judge them too and express their opinions. It is an unspoken rule: I don’t speak about bad things that you do and you don’t speak about bad things I do. Moreover, the standards expected from humans are consistently going down. … Read more