Solving Variable Velocity Water Pouring Problem with Calculus

  • Thread starter Thread starter hexlan
  • Start date Start date
  • Tags Tags
    Variable Velocity
AI Thread Summary
The discussion revolves around a problem involving variable velocity water pouring from a pitcher, where the pouring rate starts at 2 ml/s and increases based on the variable x over time. The user seeks assistance in solving the problem using calculus, specifically through integration, to determine how long it takes to pour out a gallon of water. The correct approach involves setting up the equation for the flow rate as dv/dt = 2^(1 + t/5) and integrating it to find the volume in terms of time. The integration process is acknowledged as potentially complex, but it is necessary to find the time required to empty the pitcher. Overall, the conversation highlights the application of calculus in solving real-world problems related to variable rates.
hexlan
Messages
2
Reaction score
0
I've been relearning c++ and my friend gave me a problem to try and solve programmatically. Here is the set up:

There is a pitcher with a gallon of water.
The water is being poured out beginning at a rate of 2x milliliters per second.
x begins at 1 and increases by 1 over 5 seconds.

The goal is to find out how long it takes to pour out all the water.

I finished writing a program and got an answer, but unfortunately both me and my friend are quite rusty with our calculus and have no way of checking the answer.

Could someone possibly provide an answer, or better yet go through the proper way of solving it.
 
Physics news on Phys.org
Does that mean x=1 + t/5?
WolframAlpha can integrate that (where u is the time in seconds), you just have to set the result equal to the number of milliliters in a gallon (I refuse to calculate with imperial units).

Or does the flow rate increase in steps (2, 4, 8, ... ml/s)? Then you need a sum.
 
mfb said:
Does that mean x=1 + t/5?

That is correct.
 
dv/dt = 2^x, x=1+(t/5) therefore dv/dt = 2^(1+t/5). Integrate this to find v in terms of t, when t=0, v=0. Use this to find the constant of integration. From this you can sub the volume of a gallon in ml to find the value of t(seconds). I think this should work however the integration may be a little tricky. Thanks Kyle
 
Last edited:
Hello everyone, Consider the problem in which a car is told to travel at 30 km/h for L kilometers and then at 60 km/h for another L kilometers. Next, you are asked to determine the average speed. My question is: although we know that the average speed in this case is the harmonic mean of the two speeds, is it also possible to state that the average speed over this 2L-kilometer stretch can be obtained as a weighted average of the two speeds? Best regards, DaTario
Thread 'Beam on an inclined plane'
Hello! I have a question regarding a beam on an inclined plane. I was considering a beam resting on two supports attached to an inclined plane. I was almost sure that the lower support must be more loaded. My imagination about this problem is shown in the picture below. Here is how I wrote the condition of equilibrium forces: $$ \begin{cases} F_{g\parallel}=F_{t1}+F_{t2}, \\ F_{g\perp}=F_{r1}+F_{r2} \end{cases}. $$ On the other hand...
I know that mass does not affect the acceleration in a simple pendulum undergoing SHM, but how does the mass on the spring that makes up the elastic pendulum affect its acceleration? Certainly, there must be a change due to the displacement from equilibrium caused by each differing mass? I am talking about finding the acceleration at a specific time on each trial with different masses and comparing them. How would they compare and why?
Back
Top