An object is thrown up in the air at 15 meters per second. You want to figure out how high the object will be at 2.5 seconds after its release. Answer the following questions.

Question

mathmale · Answer

From Physics, an appropriate equation of motion would be $$s=s _{0}+v _{0}t+\frac{ 1 }{ 2 }a t^2$$

mathmale · Answer

Think.  Can you figure out what those symbols represent?  Where would you find a numeric value for "a?"

a1234 · Answer

a would be acceleration, which in this case is gravity -- -9.8 m/s

mathmale · Answer

Actually, it'd be $$-9.8\frac{ m }{ \sec^2 }$$

mathmale · Answer

What do the following represent?$$t, s _{0}, v _{0}~??$$

a1234 · Answer

t = time
s0 = original altitude
v0 = initial speed

By the way, why can't we use displacement equations like d = vi*t + 1/2*a*t^2 ?

mathmale · Answer

Your "displacement equation" has precisely the same format as "mine" and is also usable.

a1234 · Answer

Ok...so t = 2.5 s and the original velocity is 0, right?