What is the perpendicular component of the rate of change?

AI Thread Summary
The discussion revolves around calculating the perpendicular component of the rate of change of a child's momentum while swinging on an elastic cord. The child has a mass of 22 kg and a horizontal speed of 6 m/s at the bottom of the swing, with the cord length being 3.70 m. Participants clarify that the perpendicular component of momentum change relates to the net centripetal force acting on the child. The initial calculation attempt of 214.05 is deemed incorrect, and suggestions include checking for significant figures and ensuring proper units are used. The correct approach involves applying the formula mv^2/r to find the perpendicular component accurately.
ohheytai
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A child of mass 22 kg swings at the end of an elastic cord. At the bottom of the swing, the child's velocity is horizontal, and the speed is 6 m/s. At this instant the cord is 3.70 m long.

At this instant, what is the perpendicular component of the rate of change of the child's momentum?
someone please help i know that the perpendicular component is 0

Homework Equations


mv^2/r

The Attempt at a Solution


i tried 22*6^s divded by 3.70
and got 214.05. but its wrong can someone help me please thanks!
 
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ohheytai said:
A child of mass 22 kg swings at the end of an elastic cord. At the bottom of the swing, the child's velocity is horizontal, and the speed is 6 m/s. At this instant the cord is 3.70 m long.

At this instant, what is the perpendicular component of the rate of change of the child's momentum?
someone please help i know that the perpendicular component is 0
you mean the horizontal component is 0, don't you? But regardless of what the horizontal component is, the problem is asking for the perpendicular component of the rate of change of the child's momentum, which is the net force acting on the child in the centripetal direction, for which it appears you have, by chance or intent, the correct equation.

Homework Equations


mv^2/r



The Attempt at a Solution


i tried 22*6^s divded by 3.70
and got 214.05. but its wrong can someone help me please thanks!
Maybe it's a significant figure thing? Try 210, no decimal points please, and don't forget the units associated with this number!
 
no it is still wrong :( someone please help!
 
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