How to Calculate Constant Acceleration and Distance?

AI Thread Summary
To calculate constant acceleration, a car accelerating from rest to 79.7 mi/h in 9.01 seconds has an acceleration of 3.95 m/s². The distance traveled during this time is calculated using the formula s = ut + 1/2 at², leading to a distance of 17.79 meters. The initial velocity (u) is zero since the car starts from rest. The discussion highlights the importance of correctly applying the formula for distance, ensuring time is squared in the calculation. Accurate application of these equations is essential for solving problems involving constant acceleration and distance.
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Homework Statement


Q1: A car accelerates uniformly from rest to a
speed of 79.7 mi/h in 9.01 s.
Find the constant acceleration (expressed
in m/s2) of the car. Answer in units of m/s2.


Q2: Find the distance (expressed in m) that the
car travels during this time. Answer in units
of m.

Homework Equations


Acceleration
Distance



The Attempt at a Solution


Q1:
79.7mi/h = 35.6m/s
35.6/9.01 = 3.95m/s2

Q2:
3.95/2 * 9.01 = 17.79m
 
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Q1 looks fine to me, Q2 though, what formulae did you use?

I would have used s = ut + \frac{1}{2} at^2

where s = displacement
u = initial velocity
t = time
a = acceleration

This is the same as what you've done except your t is not squared.
 
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