Radial Acceleration on a string

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The discussion revolves around calculating the radial acceleration of a ball on a string that breaks while being whirled in a horizontal circle. The radius of the circle is 0.250m, and the ball lands 1.90m horizontally from the point directly below where the string broke. Participants suggest using projectile motion equations to determine the initial tangential velocity (v) at the moment the string breaks, which is essential for calculating radial acceleration. There is confusion regarding the role of the angle theta in the equations, particularly how it affects the components of velocity. Clarification is provided that while theta is zero, it only affects the vertical component of velocity, not the horizontal component.
alexi_b
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Homework Statement


A ball on the end of a string is whirled around in a horizontal circle of radius 0.250m. The plane of the circle is 1.06m above the ground. The string breaks and the ball lands 1.90m (horizontally) away from the point on the ground directly beneath the ball's location when the string breaks. Calculate the radial acceleration of the ball during its circular motion.

Homework Equations


Ar = -Ac = v^2/r

The Attempt at a Solution


I see no relevance between the last two measurements and only the radius is of use, but obviously they come into play somehow. I don't know where to begin with this so any help would be appreciated!
 
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Use projectile motion equations for after the string breaks with ##v_0=v## and ##\theta=0##, where ##v## the tangential velocity the moment the string breaks
You should be able to calculate ##v_0## using projectile motion equations and the data given by the problem. Then you just plug this ##v_0=v## into the equation you have wrote in part 2. Homework Equations .
 
Last edited:
Delta² said:
Use projectile motion equations for after the string breaks with ##v_0=v## and ##\theta=0##, where ##v## the tangential velocity the moment the string breaks
You should be able to calculate ##v_0## using projectile motion equations and the data given by the problem. Then you just plug this ##v_0=v## into the equation you have wrote in part 2. Homework Equations .
If theta is equal to zero won’t the whole top part of the equation be 0 as well? And then would mean I couldn’t solve for the Vo
 
alexi_b said:
If theta is equal to zero won’t the whole top part of the equation be 0 as well? And then would mean I couldn’t solve for the Vo
if theta is 0, that only means that ##V_{0y}=0## and ##V_{0x}=V_0\cos0=V_0##
 
Delta² said:
if theta is 0, that only means that ##V_{0y}=0## and ##V_{0x}=V_0\cos0=V_0##
I’m still confused, where is the cos coming in from?
 
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