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3 years ago

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The speed of a car is decreased uniformly from 30. meters per second to 10. meters per second in 4.0 seconds. What was the car's

acceleration ?

2 answers:

Westkost [7]3 years ago

8 0

Hello!

The speed of a car is decreased uniformly from 30. meters per second to 10. meters per second in 4.0 seconds. What was the car's acceleration ?

We have the following data:

V (final velocity) = 10 m/s

Vo (initial velocity) = 30 m/s

ΔV (speed interval) = V - Vo → ΔV = 10 - 30 → ΔV = - 20 m/s

ΔT (time interval) = 4.0 seconds

a (average acceleration) = ? (in m/s²)

Formula:

$\boxed{a = \dfrac{\Delta{V}}{\Delta{T}}}$

Solving:

$a = \dfrac{\Delta{V}}{\Delta{T}}$

$a = \dfrac{-20\:\dfrac{m}{s}}{4.0\:s}$

$\boxed{\boxed{a = - 5\:\frac{m}{s^2}}}\:\:\:\:\:\:\bf\green{\checkmark}$

________________________________

$\bf\red{I\:Hope\:this\:helps,\:greetings ...\:Dexteright02!}$

masha68 [24]3 years ago

3 0

Acceleration (magnitude anyway) = (change in speed) / (time for the change) .

Change in speed = (10 - 30) = -20 m/s

Time for the change = 4.0sec

Magnitude of acceleration = -20/4 = <em>-5 m/s² </em>

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