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2 years ago

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Suppose a teenager puts her bicycle on its back and starts the rear wheel spinning from rest to a final angular velocity of 250

rpm in 5.00 s. (a) Calculate the angular acceleration in rad/s2. (b) If she now slams on the brakes, causing an angular acceleration of –87.3rad/s2, how long does it take the wheel to stop

1 answer:

shtirl [24]2 years ago

3 0

Answer: a) angular acceleration, a = 5.24rad/s^2

b) time taken for the wheel to stop, ∆t = 0.30s

Explanation:

All shown in the attachment.

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FromTheMoon [43]

Answer:

Part a)

Direction of net force is

$\theta = 46.7 degree$

Part b)

Direction of the velocity is given as

$\phi = 27.9 degree$

Explanation:

As we know that the velocity of the particle is given as

$v = 8.00 t \hat i + 3.00 t^2\hat j$

now the acceleration is given as

$a = \frac{dv}{dt}$

$a = 8.00 \hat i + 6.00 t\hat j$

now magnitude of net acceleration is given as

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$F = 3a$

$35 = 3\sqrt{64 + 36t^2}$

$t = 1.41 s$

Part a)

Now direction of net force is given as

$tan\theta = \frac{F_y}{F_x}$

$tan\theta = \frac{6t}{8}$

$tan\theta = \frac{6(1.41)}{8}$

$\theta = 46.7 degree$

Part b)

Direction of the velocity is given as

$tan\phi = \frac{v_y}{v_x}$

$tan\phi = \frac{3.00 t^2}{8.00 t}$

$tan\phi = \frac{3.00(1.41)}{8.00}$

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2 years ago

Tapping the surface of a pan of water generates 17.5 waves per second. If the wavelength of each wave is 45 cm, what is the spee

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Answer:

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Explanation:

It is given that, tapping the surface of a pan of water generates 17.5 waves per second.

We know that the number of waves per second is called the frequency of a wave.

So, f = 17.5 Hz

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Speed of the wave is given by :

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$v=17.5\times 0.45$

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So, the speed of the wave is 7.87 m/s. Hence, this is the required solution.

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2 years ago

Bill drives and sees a red light. He slows down to a stop. A graph of his velocity over time is shown below.

antoniya [11.8K]

Answer:

-2 m/s^2

Explanation:

Acceleration is equal to the slope of the graph. You just find the slope of that section. The rise is -20 and the run is 10, so you get -2.

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2 years ago

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Answer:

at y=6.29 cm the charge of the two distribution will be equal.

Explanation:

Given:

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<u>we know, the electric field due to linear charge is given as:</u>

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where:

$\lambda=$ linear charge density

r = radial distance from the center of wire

$\epsilon_0=$ permittivity of free space

Therefore,

$E_1=E_2$

$\frac{\lambda_1}{2\pi.x.\epsilon_0}=\frac{\lambda_2}{2\pi.(0.11-x).\epsilon_0}$

$\frac{\lambda_1}{x} =\frac{\lambda_2}{0.11-x}$

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Answer:

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Explanation:

if it is about electricity then its flagpole

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