# Search results

1. ### Matrices and infinite solutions

Homework Statement Find h so that: -8x + -7y = 7 16x + hy = 14 has infinitely many solutions (solve this exercise with matrices). Homework Equations - The Attempt at a Solution I converted the system to matrix form, but when I try to convert it to echelon form, I get the...
2. ### Limit of a function

Homework Statement Does lim x-> -2 (3x2+ax+a+3)/(x2+x-2) exist? If so, find the limit. Homework Equations - The Attempt at a Solution I've tried factorizing the denominator to (x+2)(x-1), but then I don't know how to proceed on the exercise. I have seen that the limit exists...
3. ### How to measure copper sulfate specific heat

Homework Statement I was wondering, how can i measure the specific heat capacity of a solution? Not the exercise, just doing an experimental work to measure it. Homework Equations q=mct The Attempt at a Solution I'm lost.
4. ### Wave pulses velocity

Homework Statement In the picture. Homework Equations I guess λ=cv? I'm not sure on this one. The Attempt at a Solution I don't know how the velocity and the displacement are related in this exercise. However, i do recall the graphs of displacement, velocity and acceleration in SMH.
5. ### Magnetic field caused by a current-carrying wire

Homework Statement In the picture. Homework Equations Right/left hand rule? The Attempt at a Solution I have tried applying the right hand rule to this situation, but they only give me the current and nothing else, so i can't determine the direction of the magnetic field in the point P.
6. ### Mass between two springs

Hello! My second time here, and this forum has really been helpful. I got a question: How could i do an experiment to study the SHM of a mass between two springs? I've tried doing it, but the mass can't complete one cycle, and friction is always a problem. Is there a way to reduce it...
7. ### Lifting Books - Potential Energy

Homework Statement A student has six books, all of them with a 4cm thickness and a weight of 30N. ¿What would be the minimum work to put the books in one pile, if the six books are in a table? Weight: 30N Thickness: 4cm. Gravity: 9.81ms-2 Homework Equations Ep=mgh Ec=(mv2)/2...
8. ### Lifting books - Potential Energy

I need help on this proble: A student has six books, all of them with a 4cm thickness and a weight of 30N. ¿What would be the minimum work to put the books in one pile, if the six books are in a table?
9. ### Momentum-related exercise

Need help on this problem: 10. A fireman is holding a hosepipe so that water leaves the pipe horizontally. The hosepipe has a constant cross-sectional area. The magnitude of the force that the fireman exerts to hold the hosepipe stationary is F. The volume of water delivered by the hose per...
10. ### Measuring gravitational force of the Earth

Hello, our teacher told us that how could we find the gravitational force of the Earth, and i wanted to do it with falling objects (Only option i got, no pendulums). Does anyone have an idea what is a free-fall apparatus? I wanted to measure it just with a cronometer, but i need more precise...