How Can I Solve These Physics Problems on Motion and Acceleration?

[Kadaj]

I can't seem to figure these problems if anyone can give me the concept and start me off that would be great.

Thanks in advance

Problem one: A car is traveling at a constant speed of 27 m/s on a highway. At the instant this car passes an entrance ramp, a second car enters the highway from the ramp. The second car starts from rest and has a constant acceleration. What acceleration must it maintain so that the two cars meet for the first time at the next exit which is 1.8 km away?

Problem two: A bus stop to pick up riders. A woman is running at a constant velocity of +5.0 m/s in an attempt to catch the bus When she is 11 m from the bus, it pulls away with a constant acceleration of +1.0 m/s^2. From this point, how much time does it take her to reach the bus if she keeps running with the same velocity?

*edit* oh and let me show you what i did so far

ok for problem one i drew a picture to visualize this and somehow came up with .405 m/s^2. I think what i did was found out the time it took to get to 1800 m with 27 m/s as its velocity and got seconds and after i did 27/66.7(which was the result from what i did previously)

with problem two i did: x=volt+1/2at^2

and got 1.86 s which i know is wrong =(

any help would be fine thanks

 

[Pyrrhus]

Oh i replied to you in the other forum.

 

[Doc Al]

Cyclovenom's response is here: https://www.physicsforums.com/showthread.php?t=45635