Everyone calls the centrifugal force a pseudo force and claims that it is not really present, even though there are so many machines listed as taking advantage of it (e.g. centrifuge, washing machine, drier). It also has the same magnitude as the centripetal force, so that they cancel each other out but I can definitely feel it every time I take a sharp turn in a car.
So can you explain whether the centrifugal force is real?
Answer
Suppose you are at a red light in your car. You apply Newton's second law on the street light. $$F=ma$$ $$F=0N, a=0ms^{-2}$$$$0N=0N$$
It works!!
Now the light turns green and you start accelerating. Suppose your acceleration is $1ms^{-2}$. According to you, you are at rest. Do you see your nose moving? Apparently not. It means your body is at rest wrt you. So street light has acceleration $-1ms^{-2}$ wrt you. Let's apply Newton's second law.
$$F=ma$$
Clearly, there is no force acting on it. And the light,say, has mass=$50kg$
$$0N=-50N$$
NOOOOOOOOOOOOO.....
Your mind just blew, right? You see that you are unable to apply Newton's second law in an accelerating frame. Let's see how can we fix it.
IF we add $-50N$ on $LHS$ we will get the correct answer.
Hence, we define pseudo force as a correction term which enables us to apply Newton's second law in accelerating frames. It has no real existence, it is just a mathematical force.
Similarly, a centripetal force is needed to make you go in a circle. If you sit there, you have to apply a force outwards which we call centrifugal force, to use Newton's laws.
Centripetal force is a force which provides acceleration towards centre, say, Tension while moving the object round with string. So if, you apply $F=ma$ from the revolving object, you have to add centrifugal force as the object is at rest wrt itself.
You can explain what you experience while turning due to you inertia which resists you change in motion.
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