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3 years ago

9

Driving at 75m/s, you hit the brakes on your new car, accelerating at a rate of -20m/s. How long will it take the car to come to

rest?

1 answer:

soldi70 [24.7K]3 years ago

5 0

Answer:

3.75s

Explanation:

Using equation of motion, t= (v-u)/a

where v=0, u=75 and a=-20

t=-75/-20=75/20=3 /.75

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A short current element dl⃗ = (0.500 mm)j^ carries a current of 5.40 A in the same direction as dl⃗ . Point P is located at r⃗ =

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Answer:

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Explanation:

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$\vec{dl}\times\vec{r}=(0.5\times10^{-3})\times(-0.730)i+(0.390)k$

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$B=1.670\times10^{-10}i+3.484\times10^{-10}k$

Hence, The magnetic field along x axis is

$B_{x}=1.670\times10^{-10}\ T$

The magnetic field along y axis is zero.

The magnetic field along z axis is

$B_{z}=3.484\times10^{-10}\ T$

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