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katrin2010 [14]

3 years ago

11

An object, initially at rest, is subject to an acceleration of 45 m/s^2. How long will it take that object to travel 1000m? Roun

d to one decimal place.

1 answer:

Romashka-Z-Leto [24]3 years ago

4 0

Answer:

6.7 seconds

Explanation:

d=(1/2)at^2

equation

1000=(1/2)45t^2.

substitute

2000=45t^2.

multiply by 2 for both sides

44.44=t^2.

divide both sides by 45

6.7=t

take the square root of both sides

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3) What is the velocity of car B when the two cars meet?

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4) What is the velocity of car A when the two cars meet?

Here we need to evaluate the velocity equation for Car A at t = 11.48s

$V_a(t) = (5m/s^2)*11.48s = 57.4 m/s$

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