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Rus_ich [418]
3 years ago
13

The brakes in a car increase in temperature by ΔT when bringing the car to rest from a speed v. How much greater would ΔT be if

the car initially had twice the speed? You may assume the car to stop sufficiently fast so that no heat transfers out of the brakes.\
Physics
1 answer:
Wewaii [24]3 years ago
4 0

Answer:

T would be two times the temperature That it was before the double so if the initial temperature was 20 it would now be 40

Explanation:

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An industrial firm has two electrical loads connected in parallel across the power source. Power is supplied to the firm at 4000
Andrei [34K]

Answer:

I = 27.65A < 40.59°

PowerFactor = 0.76

Explanation:

Current on the heating load is:

I1 = 30KW / 4KV = 7.5A < 0°

Current on the inductive load:

I2 = (150KVA*0.6) /4KV = 22.5A  with an angle of acos(0.6)=53.1°

The sum of both currents is:

It = I1 + I2 = 7.5<0° + 22.5<53.1° = 27.65<40.59°

Now, the power factor will be:

pf = cos (40.59°) = 0.76

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One of the characteristics of the planet mars that makes it very different from earth is that it does not have a large magnetic
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Explanation:

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What is the equation for the potential energy stored in a spring when it is stretched or compressed?
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Answer:

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A quantum system has three energy levels, so three wavelengths appear in its emission spectrum. the shortest observed wavelength
daser333 [38]
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An underwater scuba diver sees the Sun at an apparent angle of 43.0° above the horizontal. What is the actual elevation angle of
Inessa05 [86]

Answer:

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Explanation:

In the attachment you can clearly see the situation. The angle of elevation as seen for the scuba diver is shown in magenta, we conclude that \theta_2=90-43=47.

Using Snell's Law we can write:

n_1\sin(\theta_1)=n_2\sin(\theta_2)

\implies \sin(\theta_1)=\frac{n_2}{n_1}\sin(\theta_2),

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We thus have:

\sin(\theta_1)=n_2\sin(\theta_2)=1.333\sin(47)

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7 0
3 years ago
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