Acceleration Problem: Calculating Time Difference for Porsche vs. Honda 400 Race

[rebeccc]

A Porsche challenges a Honda to a 400 race. Because the Porsche's acceleration of 3.5 is larger than the Honda's 3.0 , the Honda gets a 50 head start. Assume, somewhat unrealistically, that both cars can maintain these accelerations the entire distance.

By how much time does the winner win?

 

[chislam]

What have you tried?

 

[rebeccc]

Pretty much everything I could think of. We have online homework and we have to submit the answer and we only have 6 attempts.. and I'm down to two. The answers I have submitted already are: 2.39, 1.5, .85, and .11

 

[chislam]

Well if you're using this formula:

$$x = v_0t + \frac{1}{2}at^2$$

Then, you should get the right answer. The only unknown in that formula is the time, which is what you are after. Simply do that for both cars and compare their times.