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LuckyWell [14K]
3 years ago
14

A police car chases a speeder along a straight road towards a cliff both vehicles move at 160km/h the siren on the police car pr

oduces sound at a frequency of 100hz calculate Doppler shift in the frequency heard by the driver in a car behind the police at 120km/h moving towards the cliff and velocity if sound in air is 330m/s
Physics
1 answer:
natta225 [31]3 years ago
4 0

Answer:

f ’= 97.0 Hz

Explanation:

This is an exercise of the doppler effect use the frequency change due to the relative movement of the fort and the observer

in this case the source is the police cases that go to vs = 160 km / h

and the observer is vo = 120 km / h

the relationship of the doppler effect is

          f ’= f₀ (v + v₀ / v- v_{s})

let's reduce the magnitude to the SI system

            v_{s} = 160 km / h (1000 m / 1km) (1h / 3600s) = 44.44 m / s

            v₀ = 120 km / h (1000m / 1km) (1h / 3600s) = 33.33 m / s

we substitute in the equation of the Doppler effect

          f ‘= 100 (330+ 33.33 / 330-44.44)

          f ’= 97.0 Hz

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Answer:

m=57.65 kg

Explanation:

Given Data

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Let the center of mass is at x distance from the canoe center and it will be towards the Ricardo cause. So the toque around the center of mass is given as

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We have to find m₂.To find the value of m₂ first we need figure out the value of.As they changed their positions the center of mass moved to other side by distance 2x.

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Substitute in the above equation we get

m_{x}=\frac{m_{1}(L/2-x)-m_{2}x }{L/2+x}\\m_{x}=\frac{80(\frac{3}{2}-0.2 )-30*0.2}{3/2+0.2}\\m_{x}=57.65 kg

4 0
3 years ago
A small plane flies at a speed of 102 km/h in still air. Suppose the wind blows out from the west (with the air moving east) at
Semmy [17]

Answer:

2.68 hours

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B.) Given that plane flies at a speed of 102 km/h in still air. And the wind blows out from the west (with the air moving east) at a speed of 46 km/h.

The plan resultant speed can be calculated by using pythagorean theorem.

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3 years ago
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If your speed changes from 10 km/h to 6 km/h then
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8 0
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