How many seconds will it take before the cars meet?

In summary, using the principle of relative velocity, we can determine that it will take approximately 977.65 seconds for the two cars, initially 17.50 km apart and traveling towards each other at speeds of 7.50 m/s and 10.40 m/s, to meet. This was calculated by converting the distance to meters, adding the speeds, and dividing by the total speed.
  • #1
Lana Elcic
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
 
Physics news on Phys.org
  • #2
You have doubts? Need an organizing/systematic principle?
 
  • #3
Bystander said:
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
Lana Elcic said:
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.
 

1. What is the formula for calculating the time it takes for two cars to meet?

The formula for calculating the time it takes for two cars to meet is t = d / (v1 + v2), where t is time, d is the distance between the two cars, and v1 and v2 are the velocities of the two cars.

2. How do you determine the distance between two cars when calculating the time it takes for them to meet?

The distance between two cars can be determined by multiplying the velocity of one car by the time it has been traveling. This will give you the distance that car has traveled. Subtract this distance from the total distance between the two cars to get the distance between the two cars at the time of meeting.

3. What units should be used when calculating the time it takes for two cars to meet?

The units used for time should be consistent with the units used for velocity and distance. For example, if velocity is measured in miles per hour and distance is measured in miles, then time should be measured in hours.

4. Can this formula be used for cars traveling in opposite directions?

Yes, this formula can be used for cars traveling in opposite directions. The only difference is that the velocities of the two cars will have opposite signs, as one car is traveling in the positive direction and the other in the negative direction.

5. Is this formula only applicable to cars or can it be used for other objects?

This formula can be used for any objects that are moving towards each other at constant velocities. It is not limited to just cars. As long as the distance and velocities are known, this formula can be used to calculate the time it takes for any two objects to meet.

Similar threads

  • Introductory Physics Homework Help
Replies
4
Views
2K
  • Introductory Physics Homework Help
Replies
2
Views
495
  • Introductory Physics Homework Help
Replies
5
Views
7K
  • Introductory Physics Homework Help
Replies
6
Views
1K
  • Introductory Physics Homework Help
Replies
9
Views
3K
  • Introductory Physics Homework Help
Replies
9
Views
3K
  • Introductory Physics Homework Help
Replies
3
Views
2K
  • Introductory Physics Homework Help
Replies
7
Views
1K
  • Introductory Physics Homework Help
Replies
8
Views
2K
  • Introductory Physics Homework Help
Replies
7
Views
2K
Back
Top