Show all work using LESSS to answer questions 1 - 3.(adsbygoogle = window.adsbygoogle || []).push({});

1. A car starts from rest and proceeds west, accelerating to a velocity of 100 km/h in exactly one minute. What was the acceleration in m/s2?

a=ΔvΔt

This is what I got for #1

L Delta A = ?

E Delta A = Ai= 27.8m/s Af= 60 seconds

S Delta A = Ai/Af = 27.8 / 60 =

S Delta A = 0.463

S Delta A = 0.5m/s2

2. A car traveling north at 50 m/s speeds up to 80 m/s by accelerating at a rate of 4.0 m/s2. What was the time required?

T= Iv/fv*a?

3. A plane traveling at 200 km/h north accelerates at 5.00 m/s2 for two minutes. What is the planes final velocity in m/s?

Final velocity = iv+ t * a

3. A plane traveling at 200 km/h north accelerates at 5.00 m/s2 for two minutes. What is the planes final velocity in m/s?

Final velocity = (Initial velocity) + (time)(acceleration)

Show your work including equation, substitution and final answer, for questions 4 – 7.

4. A boy on a bicycle travels in a straight line east and slows down from 30 m/s to 10 m/s in 5.0 s. What is his acceleration?

a=ΔivΔfv

5. A car travelling south slows down from 80 m/s to 40 m/s by accelerating at -4.0 m/s2. What time interval was required?

Time = Initial Speed/Final Speed*Acceleration?

6. A car travelling south accelerates at 3.0 m/s2 for 9.0 s and reaches a speed of 90 m/s. What was the car’s original speed?

Not sure

7. A car traveling east at an unknown speed applies the brakes and slows down at a rate of 5.0 m/s2 for 5.0 s. If the final velocity of the car is 95 m/s east, what was the original velocity of the car?

Not sure

I'm aware I need to at least try, Which i'm doing now.

Thanks in advance.

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# Homework Help: Help with Acceleration problems

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