pawn and rock for knight and bishop

It depends but not usually. It is often better to keep the two minor pieces.

In 1999, in a famous Chess Life article, Larry Kaufman examined over 80,000,000 positions and found that, on average, Q = 9.75, R = 5, B = N = 3.25, P=1.

That means swapping R + P for B + N is swapping 6 for 6.5 and is a disadvantage to the side losing the B + N.  Of course, it depends on the situation but most often is a bad idea for the B + N player. Experienced chess players come to learn from experience that making that trade at f2 or f7 on a castled position is a bad idea for the B + N owner in all but unusual cases.

The relative values of the pieces most often stated, Q = 9, R = 5, B = N = 3 are attributed to Fred Reinfeld in the 1950's.  But you can get these approximate same values from Jose Capablanca, who in 1921 while he was World Champion, wrote Chess Fundamentals where he says the B is worth more than 3:

5. Relative Value of the Pieces
Before going on to the general principles of the openings, it is advisable to give the student an idea of the proper relative value of the pieces. There is no complete and accurate table for all of them, and the only thing to do is to compare the pieces separately.
For all general theoretical purposes the Bishop and the Knight have to be considered as of the same value, though it is my opinion that the Bishop will prove the more valuable piece in most cases; and it is well known that two Bishops are almost always better than two Knights.

The Bishop will be stronger against pawns than the Knight, and in combination with pawns will also be stronger against the Rook than the Knight will be. A Bishop and a Rook are also stronger than a Knight and a Rook, but a Queen and a Knight may be stronger than a Queen and a Bishop.
A Bishop will often be worth more than three pawns, but a Knight very seldom so, and may even not be worth so much.
A Rook will be worth a Knight and two pawns, or a Bishop and two pawns, but as said before, the Bishop will be a better piece against the Rook.

Two Rooks are slightly stronger than a Queen. They are slightly weaker than two Knights and a Bishop, and a little more so than two Bishops and a Knight.
The power of the Knight decreases as the pieces are changed off. The power of the Rook, on the contrary, increases.
The King, a purer defensive piece throughout the middlegame, becomes an offensive piece once all the pieces are off the board, and sometimes even when there are one or two minor pieces left. The handling of the King becomes of paramount importance once the endgame stage is reached."

INCORRECT GRAMMER CORRECT SPELLING "Is it smart to take a pawn and a rock on the on the king side for a knight and a bishop.Geeeeeeez.Why don't Chess.com members have incorrect spelling?

I really don't know.

pawn and -rock-. rofl

rock paper scissors lizard spock