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3 years ago

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The parking brake on a 1000 kg Cadillac has failed, and it is rolling slowly, at 1 mph , toward a group of small children. Seein

g the situation, you realize you have just enough time to drive your 2000 kg Volkswagen head-on into the Cadillac and save the children.

1 answer:

GalinKa [24]3 years ago

6 0

Um of momenta = 0( Since both the cars stop)
<span>Let m1 be the mass of the cadillac and m2 be the mass of the volkswagen. </span>
<span>then, v1=speed of cadillac and v2=speed of volkswagen. </span>
<span>Therefore, (m1)*(v1) + (m2)*(v2) = 0 </span>
<span>Substituting, </span>
<span>(1000*4) + (2000*v2) = 0 </span>
<span>4000 = - 2000 v2 </span>
<span>Therefore, v2= - 2 m/s. </span>

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Explanation:

We can answer this exercise using Gauss's law

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field flow is directly proportionate to the charge found inside it, therefore if we place a Gaussian surface outside the plastic spherical shell. the flow must be zero since the charge of the sphere is equal induced in the shell, for which the net charge is zero. we see with this analysis that this shell meets the requirement to block the elective field

From the same Gaussian law it follows that if the sphere is not in the center, the only effect it has is to create more induced charge at the closest points, but the net face remains zero, so it has no effect on the flow , so no matter where the sphere is, the total induced charge is always equal to the charge on the sphere.

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A car is going south on I-69 at 33 m/s (74 mph). The car has good brakes so its maximum braking acceleration is – 8.5 m/s^2 . Tr

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Answer:

1.69515 seconds

Explanation:

t = Time taken

u = Initial velocity

v = Final velocity

s = Displacement

a = Acceleration

$v^2-u^2=2as\\\Rightarrow s=\frac{v^2-u^2}{2a}\\\Rightarrow s=\frac{0^2-33^2}{2\times -8.5}\\\Rightarrow s=64.06\ m$

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The reaction time cannot be more than 1.69515 seconds

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3 years ago

An apple from the top branch of the tree and an apple from the bottom branch of a tree fall at the same time. Which apple will h

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3 years ago

Write down the (real) electric and magnetic fields for a monochromatic plane wave of amplitude E0 , frequency w, and phase angle

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Answer:

a) the oscillation of this field is in phase, when the magnetic field goes in the negative direction of y, the elective field goes in the positive direction of the z axis

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Explanation:

a) the polarization the determined wave oscillates the electric field, which is the z axis

As the wave travels on the negative x-axis and the magnetic field is perpendicular, this field goes on the positive y-axis

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3 years ago

A ray of light traveling through air strikes a piece of diamond at an angle of incidence equal to 56 degrees. Calculate the angu

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Answer:

The angle of separation is $\Delta \theta = 0.93 ^o$

Explanation:

From the question we are told that

The angle of incidence is $\theta _ i = 56^o$

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The refractive index of red light in diamond is $n_r = 2.41$

The wavelength of violet light is $\lambda _v = 400nm = 400*10^{-9}m$

The wavelength of red light is $\lambda _r = 700nm = 700*10^{-9}m$

Snell's Law can be represented mathematically as

$\frac{sin \theta_i}{sin \theta_r} = n$

Where $\theta_r$ is the angle of refraction

=> $sin \theta_r = \frac{sin \theta_i}{n}$

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$sin \theta_r__{v}} = \frac{sin \theta_i}{n_v}$

substituting values

$sin \theta_r__{v}} = \frac{sin (56)}{2.46}$

$sin \theta_r__{v}} = 0.337$

$\theta_r__{v}} = sin ^{-1} (0.337)$

$\theta_r__{v}} = 19.69^o$

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$sin \theta_r__{R}} = \frac{sin \theta_i}{n_r}$

substituting values

$sin \theta_r__{R}} = \frac{sin (56)}{2.41}$

$sin \theta_r__{R}} = 0.344$

$\theta_r__{R}} = sin ^{-1} (0.344)$

$\theta_r__{R}} = 20.12^o$

The angle of separation between the red light and the violet light is mathematically evaluated as

$\Delta \theta = \theta_r__{R}} - \theta_r__{V}}$

substituting values

$\Delta \theta =20.12 - 19.69$

$\Delta \theta = 0.93 ^o$

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4 years ago