Is this equation for acceleration on this website wrong?

[Physicsy]

Greetings, I've been learning the mathematics of classical physics from a website called "A physiscs teacher" (http://aphysicsteacher.blogspot.com/search/label/acceleration). While looking through the equations on the acceleration i think i found a mistake made by the website.

A bus starts from rest and accelerates at a rate of 2.5 m/s2 for a time of 50 s. Determine the distance traveled by the bus during the acceleration phase.

Now let us identify the different variables involved.

u the initial speed = 0 m/s

t time taken = 50 s

a acceleration = 2.5 m/s2

s distance traveled = ?

If we want calculate s the distance traveled we will have to use the second equation of motion

S = ut + 1/2at2

Substituting the different values we get

S = ut + 1/2at(squared)

= o*50 + 0.5 *50(squared)

= 0 + 0.5*2500

=1250 m

My problem with this question comes in when after the values have been substituated.
= o*50 + 0.5 *50(squared), I am kinda new to the mathematical side of physics but shouldn't the acceleration (2.5) have been substituated in as well to make it
= o*50 + 0.5 *2.5 *50(squared) get an answer of 3125?

 

[Stonebridge]

If
a=2.5 m/s²
t=50s
u=0
then
s = ut + ½at²
s = 0 + ½ x 2.5 x 50²
s = 3125m

 

[Doc Al]

S = ut + 1/2at(squared)

OK.

= o*50 + 0.5 *50(squared)

Oops!

My problem with this question comes in when after the values have been substituated.
= o*50 + 0.5 *50(squared), I am kinda new to the mathematical side of physics but shouldn't the acceleration (2.5) have been substituated in as well to make it
= o*50 + 0.5 *2.5 *50(squared) get an answer of 3125?

Of course. The webpage goofed in leaving out the acceleration. (It was obviously an oversight.) Send the author an email suggesting that he correct the page! He will appreciate the correction.

Good catch.