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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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patriot [66]

Answer:

Thus the time taken is calculated as 387.69 years

Solution:

As per the question:

Half life of ^{3890}Sr\, t_{\frac{1}{2}} = 28.5 yrs

Now,

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By using the formula:

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where

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Taking log on both the sides:

- 4 = \frac{t}{28.5}log\frac{1}{2}

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5 0
3 years ago
An 800 kg fishing boat going south at 12 m/s runs into a stopped pontoon boat (1400 kg). The boats stick together and move south
kykrilka [37]

Answer:

the velocity of the boats after the collision is 4.36 m/s.

Explanation:

Given;

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initial velocity of the boat, u₂ = 0

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9600 = 2200v

v = 9600/2200

v = 4.36 m/s

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Answer:

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