Velocity in uniform circular motion

AI Thread Summary
The discussion focuses on calculating the speed and acceleration of a point on the edge of a Ferris wheel with a radius of 20.0m, completing one revolution in 8.42 seconds. The speed is calculated using the formula v = 2πr/T, resulting in approximately 14.92 m/s, which corrects earlier calculations of 19.00 m/s. The x component of acceleration at the top of the circle is confirmed to be zero, as acceleration only acts towards the center. The y component of acceleration is calculated as -18.05 m/s², with the negative sign indicating direction towards the center of the wheel. Overall, the calculations highlight the importance of correctly applying formulas and understanding directional components in circular motion.
waldvocm
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a Ferris wheel has a radius of 20.0m and it completes 1 revolution in 8.42 seconds

a) what is the speed of a point on the edge of the wheel?

The circle is divided into 8 triangles. I have determined from that that the arcs of the circle (8 of them) each equal 20m. Because the triangles are similar and each side of the triangle will equal 20m. Is my thinking here correct?

so velocity equals 20/8.42=19.00

b)The x component of acceleration at the top of the circle would equal 0. Correct?

c)The y component of acceleration at the top of the circle would equal a=v^2/r 19.00^2/20.00=-18.05 since the acceleration vector is pointing toward the center of the circle it is negative.

Is this correct?
 
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I have a change in the velocity
v=2pir/t
v=14.92

acceleration would equal 11.14
 
waldvocm said:
a Ferris wheel has a radius of 20.0m and it completes 1 revolution in 8.42 seconds

a) what is the speed of a point on the edge of the wheel?

The circle is divided into 8 triangles. I have determined from that that the arcs of the circle (8 of them) each equal 20m. Because the triangles are similar and each side of the triangle will equal 20m. Is my thinking here correct?

so velocity equals 20/8.42=19.00

b)The x component of acceleration at the top of the circle would equal 0. Correct?

c)The y component of acceleration at the top of the circle would equal a=v^2/r 19.00^2/20.00=-18.05 since the acceleration vector is pointing toward the center of the circle it is negative.

Is this correct?

a)v=2\pir/T=2*\pi*20/8.42=14.92m/s
and the length of the arcs will equal circumference divided by 8
b)do u mean the horizontal component? yes that would equal zero as only acceleration is towards center of Ferris wheel
c)yes but the v value is wrong. look at part my explanation for part a. and as for the negative sign that depends on how u assign upwards and downwards direction. it would be better to say downwards or to center of the wheel.

EDIT: don't know why my pis are above. they shouldn't be lol
 
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