# Homework Help: Can someone help with these problems?

1. Jan 20, 2010

### tintin

can someone help with these problems??

1)Two cars, A and B are traveling in the same direction, although the car A is 100 m behind the car B. The speed of the car A is 24.7 m/s and the speed of the car B is 18.8 m/s. How much time does it take for the car A to catch the car B ? [Hint: What must be true about the displacements of the two cars when they meet?]

2)A streetcar named A travels between two stations 0.64 km apart. Leaving the first station, it accelerates for 11.0 s at 1.0 m/s2 and then travels at a constant speed until it is near the second station, when it brakes at 2.0 m/s2 in order to stop at the station. How long did this trip take? [Hint: What's the average velocity?]

3)Find the point of no return for an airport runway of 1.11 miles in length if a jet plane can accelerate at 10.7 ft/s2 and decelerate at 7.16 ft/s2. The point of no return occurs when the pilot can no longer abort the takeoff without running out of runway?

What length of time is available from the start of the motion in which to decide on a course of action?

2. Jan 21, 2010

### tiny-tim

Last edited by a moderator: Apr 24, 2017