You're close, but there's a small mistake in your formula. The correct formula is:
r = (m * ω^2) / (g * sin(θ) + ω^2 * cos(θ))
where m = 0.0728 kg, ω = 7.99 rad/s, g = 9.8 m/s^2, and θ = 17.1°.
Plugging in the given values, we get:
r = (0.0728 * 7.99^2) / (9.8 * sin(17.1) + 7.99^2 * cos(17.1))
r = (0.0728 * 63.8401) / (9.8 * 0.29366 + 63.8401 * 0.95676)
r = 4.64737 / (2.8763 + 61.06086)
r = 4.64737 / 63.93716
r = 0.0726 m
The correct answer should be approximately 0.0726 m. It seems that there might be an error in the choices provided. Check with your instructor or the source of the problem to verify the correct answer.
A girl with a 72.8 g yo-yo is swinging it in a horizontal circle at an angular velocity of 7.99 rad/s. If the string is tilted down at an angle of 17.1°, what must the length of the yo-yo string be?
so i tried doing r = (0.0728)(7.99)^2/(9.8sin17.1 + 9.8cos17.1)
i got 0.379m
i don't feel like this right as my answer is none of the choices provided
the choices are :
0.522 m
0.0380 m
0.0533 m
0.161 m
what am i doing wrong?
1 answer
0 answers