Help please?
Which kinematics equation would you use for the following problem: A car traveling at 30m/s begins to gain speed at the rate of 4.0m/s^2. How far will the car travel in 2.0 seconds?

Question

Help please?
Which kinematics equation would you use for the following problem: A car traveling at 30m/s begins to gain speed at the rate of 4.0m/s^2. How far will the car travel in 2.0 seconds?

yanasidlinskiy · Answer

$$v^2=v _{0} ^2+2ad$$

yanasidlinskiy · Answer

Is it that one?

phi · Answer

I would expect an equation that shows distance as a function of time.

yanasidlinskiy · Answer

So.... would this one work then?$$d= 1/2(v+v _{0})t$$

phi · Answer

I know 
v= a t
d = ½ a t^2  (with initial v0 = 0)
d= v t (with initial d0 = 0)

so I would use
d= ½ a t^2 + v0 t

phi · Answer

if we put in numbers
d = 2 t^2 +30t

yanasidlinskiy · Answer

So would I subtract 30t?

phi · Answer

I don't understand the question.

yanasidlinskiy · Answer

Yea, It's kinda confusing me too. @jigglypuff314 maybe ya can help?

jigglypuff314 · Answer

You just needed to indentify the kinematic equation that you want
that would be the one with $v$ (the final/ending velocity) missing

$ d = v_0*t + \frac{1}{2}*a*t^2$