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1 year ago

11

Paul and Ivan are riding a tandem bike together. They’re moving at a speed of 5 meters/second. Paul and Ivan each have a mass of

50 kilograms. What can Paul do to increase the bike’s kinetic energy?
A. He can let Ivan off at the next stop.
B. He can pedal harder to increase the rate to 10 meters/second.
C. He can reduce the speed to 3 meters/second.
D. He can pick up a third rider.

2 answers:

Tresset [83]1 year ago

8 0

Answer: Well they could go down a hill to gain more kinetic energy, or the answer can just be B. He can pedal harder to increase the rate to 10 meters/second. I hope I helped you.

GaryK [48]1 year ago

4 0

Answer:

the answer is probably reducing the speed, hope i helped! :D

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Answer:

La velocidad angular del niño y del carrusel cuando se mueven juntos es 0.208 radianes por segundo.

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Asumamos que tanto el niño como el carrusel no tienen carga externa aplicada sobre aquellos, de modo que se puede aplicar el Principio de Conservación de la Cantidad de Movimiento Angular:

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Donde:

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$v$ - Velocidad lineal inicial del niño, medida en metros por segundo.

$R$ - Radio máximo del carrusel, medida en metros.

$I$ - Momento de inercia del carrusel, medida en kilogramo-metros cuadrados.

$\omega$ - Velocidad angular final del sistema niño-carrusel, medida en radianes por segundo.

Si sabemos que $m = 25\,kg$ , $v = 2.5\,\frac{m}{s}$ , $R = 2\,m$ y $I = 500\,kg\cdot m^{2}$ , tenemos que la velocidad angular final es:

$\omega = \frac{m\cdot v\cdot R}{m\cdot R^{2}+I}$

$\omega = \frac{(25\,kg)\cdot \left(2.5\,\frac{m}{s} \right)\cdot (2\,m)}{(25\,kg)\cdot (2\,m)^{2}+500\,kg\cdot m^{2}}$

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2 years ago

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1 year ago

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Answer:

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to find out

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solution

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