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See also Simple Harmonic Motion - What are the units for $\omega_0$ ? and https://en.wikipedia.org/wiki/Joule#Confusion_with_newton-metre Here's a somewhat shorter explanation reflecting my own (possibly incorrect) intuition: Radians aren't "real" units; they're just a trick to keep track of which quantities involve angles and which don't, since it's ...


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As soon as the ball is released from the rod, it starts going in a tangential direction. Since there are no external forces on the system, the linear momentum of the system (ball + motor) must be conserved and the motor starts moving in the opposite direction of the ball with some velocity (depending upon the masses of ball and motor), so that the linear ...


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The direction of the inertia propagation is the direction of the velocity. Any acceleration can be applied to change the velocity. If the acceleration has the same direction of the velocity you will change only its modulo, but if you want to change the direction of the velocity (which is your "line of inertia") you need "a force that push from the side" or, ...


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The centripetal force can actually be measured. If you take the slingshot as an example, while rotating the end-mass you can measure a tension in the stings of the slingshot. If you stop the motion of the end-mass at a certain point in time, you can observe a velocity of the mass, that is tangential to the circular path it is taking over time. The strings ...


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A particle does not have to move in the direction of the acceleration. Acceleration is change in velocity, so the change in velocity is in the direction of acceleration. Velocity, being a vector, obeys certain Laws of vector addition(see traingle law and parallelogram law of vector addition). For example, if two forces(another vector) of equal magnitude are ...


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There are several issues occurring here- none of which require a "fictitious force" to resolve. 1) the acceleration on the shot cannot operate in the direction of it's velocity as the shot in the sling maintains a constant distance from the slinger while it is being "slung". 2) there is no "centrifugal" force on the shot... the shot attempts to follow ...


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I think your confusion with the slingshot is this: when you move your hand in circles to keep the slingshot moving in a circle you need some force, so you feel the weight of the projectile. But you where taught that according to Newton, things want to keep going in a straight line and inertia is this tendency to "not want to move or change direction". So ...


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Okay, let's lay some ground rules: An object that does not experience any force will fly in a straight line A force applied to an object will change its momentum toward the direction of the force. Now, the trick with circular motion is that both the direction of motion and the direction of the force change simultaneousely, such that the inward cetripetal ...


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Momentum is a vector, and the job of a force is to change it, in magnitude and direction. The ball has tangential momentum at any point, and when the force is perpendicular only the direction of momentum is affected. You can think of the force as a reaction force needed to keep the ball in a circle, and since it is perpendicular to the direction of motion, ...


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The direction of acceleration is the same direction for the propagation of inertia usually! This is where you are wrong. Direction of propagation is the direction in which the body is currently moving or rather, changing position. So it is the direction of infinitesimal displacement $d\vec x$ at that instant. Now what makes you think that direction of ...


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Fictitious forces naturally arise in non-inertial (accelerating) reference frames and you have to be careful with them. In this example, it only leads to confusion. $F = ma$ tells us that when the (total) force is zero, the object will continue in a straight line. It's not the centripetal force, but the absence of a centripetal force that makes the object ...



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