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mr_godi [17]
3 years ago
12

A bicycle rider traveling east at 10 km/hr sees a blue car pass her appearing to travel west at 50 km/hr. What is the blue car's

apparent speed for an observer riding in a red car traveling 15 km/hr west relative to the Earth? g
Physics
1 answer:
BigorU [14]3 years ago
8 0

Answer:

v_{bR} = 25 km/h towards west

Explanation:

As we know that the speed of the blue car as appear to the bicycle rider is given as

v_{bc} = 50 km/h towards west

also it is given that bicycle is moving at speed of 10 km/h towards East

so here we have

v_{bc} = v_b - v_c

so we have

v_b = v_{bc} + v_c

v_b = -50 + 10 = 40 km/h towards west

now speed of the red car is given as 15 km/h towards west

so here the relative speed of blue car with respect to red car is given as

v_{bR} = v_b - v_R

v_{bR} = 40 - 15 = 25 km/h towards west

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That statement is true

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Explanation:

Given that,

Distance 1, r = 100 m

Intensity, I_1=1.24\times 10^{-8}\ W/m^2

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Let I' is the intensity at r'. So,

I'=\dfrac{P}{4\pi r'^2}............(2)

From equation (1) and (2) :

I'=\dfrac{Ir}{r'^2}

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3 years ago
a 42.3 kg girl and a 7.93 kg sled are on the surface of a frozen lake, 15.0m apart and linked by a rope, but not moving yet. the
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Answer:

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Explanation:

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Answer:

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It is given that, a small metal ball is suspended from the ceiling by a thread of negligible mass. The ball is then set in motion in a horizontal circle so that the thread’s trajectory describes a cone as shown in attached figure.

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