# [SOLVED] Equations of Motion

• May 17th 2010, 02:38 AM
unstopabl3
[SOLVED] Equations of Motion
This is just something which has been bothering me and want your expertise on it.

Initial Velocity = 0
Acceleration = 1
Distance = 3

Find the time taken to cover that distance.

So generally I would use the second equation of motion to get an answer

t=2.45s

But why don't I get the same answer when I try to solve it in this way...

$a=\frac{v}{t}$ and $v=\frac{d}{t}$

Thus,

$a=\frac{d}{t}/t$

$a=\frac{d}{t^2}$

$1=\frac{3}{t^2}$

$t=1.73s$

What am I doing wrong? Why don't the answers match?
• May 17th 2010, 03:43 AM
mr fantastic
Quote:

Originally Posted by unstopabl3
This is just something which has been bothering me and want your expertise on it.

Initial Velocity = 0
Acceleration = 1
Distance = 3

Find the time taken to cover that distance.

So generally I would use the second equation of motion to get an answer

t=2.45s

But why don't I get the same answer when I try to solve it in this way...

$a=\frac{v}{t}$ and $v=\frac{d}{t}$ Mr F says: These equations give average values.

Thus,

$a=\frac{d}{t}/t$

$a=\frac{d}{t^2}$

$1=\frac{3}{t^2}$

$t=1.73s$

What am I doing wrong? Why don't the answers match?

..
• May 17th 2010, 04:39 AM
unstopabl3
Oh yes! I completely overlooked that bit!

Thanks ;)