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3 years ago

If a runner decreases his velocity from 0m/s to +20m/s in 2.0s, what is was his average acceleration?

Physics

1 answer:

Brrunno [24]3 years ago

5 0

Answer:

-10 m/s²

Explanation:

Average acceleration is change in velocity over change in time.

a = (v − v₀) / (t − t₀)

a = (0 m/s − 20 m/s) / (2 s − 0 s)

a = -10 m/s²

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3 years ago

A 30-m-long rocket train car is traveling from Los Angeles to New York at 0.5c when a light at the center of the car flashes. Wh

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Given that,

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So, The two events are simultaneous and the bell and siren are the simultaneous events for a passenger seated in the car.

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The proper time in this case is

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Put the value in the equation

$\Delta t_{2} = \dfrac{0-\dfrac{0.5c\times30}{c^2}}{\sqrt{1-\dfrac{0.5^2c^2}{c^2}}}$

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$\Delta t_{2}=-5.77\times10^{8}\ s$

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