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In Bernoulli theorem physics we say that pressure is low when velocity is high but we feel pressure when fluid hits us why?

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This shows a misunderstanding of pressure in the Bernoulli relation as well as a misunderstanding of how feelings work. Completely disregarding Bernoulli for a moment, let's say I touch you and then I punch you. Would you not feel the touch just because the punch is larger? This isn't relevant to Bernoulli, but I just want to point this out to you that relative softness does not mean undetectable.

In any case we don't need to think about the Bernoulli equation here really. If I have a high pressure pushing on the fluid at one place and a lower pressure pushing on the fluid at another place, which way will the fluid accelerate? Well, it will accelerate in the direction of decreasing pressure, so the velocity will increase as the pressure decreases.

This low pressure is not the pressure you would feel if this high-velocity stream were to hit you. The pressure you would feel is called the "stagnation pressure", and you can get an expression for it using the Bernoulli equation. I will leave this as an exercise to you to research/figure out.

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The fluid velocity actually slows down to zero when it hits you. You feel stagnation pressure.

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The other answers cover the fluid mechanics perspective; but you can also come to the same conclusion with Newton's laws.

The water has a momentum travelling towards your hand, greater velocity and mass will be more momentum. After the collision, it is travelling away from your hand in some direction, generally with less velocity than it hits your hand. This change in momentum comes from the interaction with your hand, which also imparts momentum and a force onto your hand, which you feel as the pressure. This should be apparent, because without the force of your hand Newton's laws say the water would continue moving forward instead of bouncing off your hand.

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