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BabaBlast [244]

2 years ago

14

two people, each with a mass of 70 kg, are wearing inline skates and are holding opposite ends of a 15m rope. One person pulls f

orward on the rope by moving hand over hand and gradually reeling in more of the rope. In doing so, he exerts a force of 35N [backwards] on the rope. This causes him to accelerate toward the other person. Assuming that the friction acting on the skaters is negligible, how long will it take for them to meet? Explain your reasoning.

1 answer:

Zina [86]2 years ago

5 0

Answer:

7.75 s

Explanation:

Newton's second law:

∑F = ma

35 N = (70 kg) a

a = 0.5 m/s²

Given v₀ = 0 m/s and Δx = 15 m:

Δx = v₀ t + ½ at²

(15 m) = (0 m/s) t + ½ (0.5 m/s²) t²

t = 7.75 s

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Answer:

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Explanation:

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$\omega_1 = 2\pi(\frac{610}{60})$

$\omega_1 = 63.88 rad/s$

similarly final angular speed is given as

$\omega_f = 2\pi f_2$

$\omega_2 = 2\pi(\frac{837}{60})$

$\omega_2 = 87.65 rad/s$

angular acceleration of the turbine is given as

$\alpha = 5.9 rad/s^2$

now we have to find the angular displacement is given as

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$\theta = (63.88)(3.2) + (\frac{1}{2})(5.9)(3.2^2)$

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2 years ago

In lab, your instructor generates a standing wave using a thin string of length L = 1.65 m fixed at both ends. You are told that

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Answer:

The maximum transverse speed of the bead is 0.4 m/s

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now we have

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$N = \frac{2(1.65)}{1.10}$

$N = 3$

now we have

$R = 2A sin(kx)$

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$R = 7.3 sin(1.82 \pi x)$

now at x = 13.8 cm

$R = 7.3 sin(1.82 \pi (0.138))$

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now we have

$f = \frac{v}{\lambda}$

$f = \frac{13.5}{1.1}$

$f = 12.27 Hz$

now maximum speed is given as

$v_y = R\omega$

$v_y = (5.18 \times 10^{-3})(2\pi(12.27))$

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1 year ago

As a youngster, you drive a nail in the trunk of a young tree that is 3 meters tall. The nail is about 1.5 meters from the groun

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Answer:

15m

Explanation:

Hello! first to solve this problem we must find that so much that the tree grew in the 15 years this is achieved by dividing the height of the tree before and after

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2 years ago

A piano string sounds a middle A by vibrating primarily at 220 Hz.a)Calculate its period.b)Calculate its angular frequency.c)Cal

chubhunter [2.5K]

a) 4.5 ms

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$T=\frac{1}{f}$

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For the note in this problem, f = 220 Hz, so the period of the wave is

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b) 1381.6 rad/s

The angular frequency is given by:

$\omega=2 \pi f$

where f is the frequency.

In this problem, f = 220 Hz, so the angular frequency is

$\omega=2 \pi (220 Hz)=1381.6 rad/s$

c) 1.1 ms

The frequency of the "high A" is four times the frequency of the piano string, so

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1 year ago

Which combination of initial horizontal velocity, (vh) and initial vertical velocity, (vv) results in the greatest horizontal ra

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$R = v_h(\frac{2v_v}{g}$

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now the range is given as

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so we will have

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8 0

2 years ago