# Physics Test Tomorrow

1. Sep 20, 2015

### Chatito

1. Object 1 starts at 25 m and moves with a velocity of –5.5 m/s . Object 2 starts at 13 m and moves directly toward object 1. The two objects collide 0.65 s after starting. I need to find when they both collide and the velocity of Object 2

2. I don't know much but I know the displacement formula is deltax=x_f - x_i

3. I did 25/13=1.92 and -5.5/0.65=-8.46. I know this is wrong but this is my work and I hope to find an answer

2. Sep 20, 2015

### Staff: Mentor

You have two objects, both moving at constant velocities.
Write an expression for the distance Object 1 covers.
Write an expression for the distance Object 2 covers.
What is the total distance the two objects cover?
At what point does Object 1 collide with Object 2?

3. Sep 20, 2015

### RUber

Is this a 1D problem? Object 1 is moving downward and Object 2 is moving upward (no gravity?), right?
The -5.5 / 0.65 = -8.46m gives you how far Object 1 moved in the time. So by deductive reasoning, you should know how far Object 2 travelled in the same .65 seconds.

4. Sep 20, 2015