Solve it: Catch the Bus with Constant Velocity?

In summary, the runner is attempting to catch the bus at a constant velocity, but they lack any information about how to do so. They need to choose an origin for their coordinate system and figure out what x-coordinate the bus and runner are at at the start of the motion. Once they have that information, they can figure out what t-coordinate the bus is at.
  • #1
jdenn
6
0
Hi, I've got a big probllem:

When you are 20m away from your bus it begins accelerating a 3m/s/s (from rest). What constant velocity should you run at to catch the bus.

HELP!
Please!
jason
 
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  • #2
theres i big chance no one will help you unless you show an attempt
 
  • #3
Yep, you have to show that you've made an attempt.
 
  • #4
Tom Mattson said:
Yep, you have to show that you've made an attempt.
thats the think I have no idea where to begin

The fruit of my labors is:
me:
Vi=?
Vf=?
t=?
a=0
d=to busbus:
Vi=0
Vf=?
t=?
a=3m/s^2
d=to bus
This enough? because otherwise i am sol
 
Last edited:
  • #5
Try drawing two pictures; the first showing the initial conditions, and the second showing the final conditions when you've caught the bus.

Once you've drawn the pictures, make sure you listed all your knowns.

List your kinematics formulas so you can see what you have to work with.

And don't forget to note your initial and final position.

Try choosing your initial position as zero, which would make the initial position of the bus 20 m.
 
  • #6


*melinda* said:
Try drawing two pictures; the first showing the initial conditions, and the second showing the final conditions when you've caught the bus.
Once you've drawn the pictures, make sure you listed all your knowns.
List your kinematics formulas so you can see what you have to work with.
And don't forget to note your initial and final position.
Try choosing your initial position as zero, which would make the initial position of the bus 20 m.
i have drawn a picture, listed my formulas( no idea which 1 to use though)
 
  • #7
You have yet to make use of that 20m in the problem statement. Let the motion be along the x-axis.

Can you fill in the following information?

Runner: xi=?
Bus: xi=?
 
  • #8
Tom Mattson said:
You have yet to make use of that 20m in the problem statement. Let the motion be along the x-axis.
Can you fill in the following information?
Runner: xi=?
Bus: xi=?
ive been working more but all i have still is:thats the think I have no idea where to begin

me:
Vi=?
Vf=Vi (constant)
t=?
a=0
d=to bus-20


bus:
Vi=0
Vf=?
t=?
a=3m/s^2
d=to me+20
 
  • #9
In order to answer my question, you need to choose an origin for the coordinate system. Let's just put the runner's initial position at the origin, and let the bus sit to the right of the runner.

Now can you fill in those values?
 
  • #10
me:
Vi=?
Vf=Vi (constant)
t=?
a=0
d=distance runbus:
Vi=0
Vf=?
t=?
a=3m/s^2
d=to run-20
 
  • #11
What I am asking you to do is assign an x-coordinate to both the runner and the bus initially. Do you know what a coordinate on a graph is?
 
  • #12
x would be distance and y would be time right?
 
  • #13
In the usual notation, x is distance and t is time. So if you have motion in 1 dimension, and we say that the motion is along the x-axis, and we say that the runner starts at the origin and that the bus starts out 20 meters to the right of the runner, then can you please tell me what the initial x-coordinate of both the runner and the bus are?

We're happy to help with homework, but you have to work with us.
 

Related to Solve it: Catch the Bus with Constant Velocity?

1. What is constant velocity?

Constant velocity is the rate of change of an object's position over time, where the object moves at a consistent speed in a straight line.

2. How do you solve the "Catch the Bus" problem with constant velocity?

This problem can be solved using the formula d = vt, where d is the distance, v is the velocity, and t is the time. Rearranging the formula to solve for t, we have t = d/v. Plug in the given values for d and v to find the time it takes to catch the bus.

3. Can you catch the bus if you start too late?

It depends on the distance between you and the bus stop and the speed of the bus. If the distance is short and the bus is moving slowly, you may still be able to catch it. However, if the distance is long and the bus is moving quickly, it may be impossible to catch the bus if you start too late.

4. What if the bus is moving at a constant velocity and I am not?

In this case, you would need to calculate the relative velocity between you and the bus. This can be done by subtracting your velocity from the bus's velocity. Then, use the same formula d = vt to find the time it takes for you to catch the bus.

5. Can this problem be solved with a different formula?

Yes, this problem can also be solved using the formula v = (d2 - d1)/(t2 - t1), where v is the average velocity, d1 and t1 are the initial distance and time, and d2 and t2 are the final distance and time. However, this formula assumes constant acceleration, so it would not be accurate in the case of constant velocity.

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