How many seconds will it take before the cars meet?

  • Thread starter Lana Elcic
  • Start date
  • #1
40
0

Homework Statement


Two cars are initially 17.50 km apart on a straight road. If the cars are moving toward each other, car 1 with a speed of 7.50 m/s and car 2 with a speed of 10.40 m/s, how many seconds will it take before the cars meet? Round your answer to three significant figures.

Homework Equations


Don't know

The Attempt at a Solution


Converted to 17,500 m for the distance apart.
I added 7.50 and 10.40; Then I divided 17,500 by 17.9 seconds
=977.65 seconds
 

Answers and Replies

  • #2
Bystander
Science Advisor
Homework Helper
Gold Member
5,216
1,238
You have doubts? Need an organizing/systematic principle?
 
  • #3
40
0
You have doubts? Need an organizing/systematic principle?

I wanted to see if it was right because I didn't use any formulas, I just kinda thought about it.
 
  • #4
haruspex
Science Advisor
Homework Helper
Insights Author
Gold Member
2020 Award
36,384
6,929
I wanted to see if it was right because I didn't use any formulas, I just kinda thought about it.
You have one typo, you wrote 17.9 seconds instead of 17.9 m/s.
If you want to relate your method to a principle, it would be that of relative velocity. Or, equivalently, a change to a different inertial reference frame.
 

Related Threads on How many seconds will it take before the cars meet?

Replies
3
Views
4K
Replies
4
Views
839
Replies
1
Views
3K
Replies
6
Views
14K
  • Last Post
Replies
4
Views
775
  • Last Post
Replies
4
Views
3K
Replies
19
Views
19K
Replies
5
Views
1K
Replies
8
Views
2K
Top