Recent content by eliassiguenza

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    Solving Rod Slipping: Find x min with Tension & Friction

    yes that's the diagram how silly of me! oh god i forgot... yeah that's the one! cable one is just like the red one
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    Solving Rod Slipping: Find x min with Tension & Friction

    Homework Statement a uniform rod of length 4.0m of mass M is supported by a cable which is under tension T. The other end rests against as wall, where it is held by friction. The coefficient of static friction is 0.5. An additional mass M is hung from the rod at a distance x from the wall...
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    How Does a Nuclear Explosion Affect Shock Wave Radius?

    Homework Statement In a nuclear explosion there is a very quick release of energy in a small region of space. This produces a spherical shock wave, with the pressure inside the shock wave being thousands of times greater than the initial air pressure. From wave theory it is found that the...
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    Calculating Change in Entropy: 1100 kg Cars Colliding at 75km/hr

    Also forgot to mention... you have an inelastic collision where two masses have momentum.! Remember that there is a release of energy in the form of heat because of the collision. I think that's the key for you to plug the formula as mentioned above. However that guy who said w is work WRONG...
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    Calculating Change in Entropy: 1100 kg Cars Colliding at 75km/hr

    Entropy can be calculated as: S = k ln W ( w not as in work) also you can use S = Q/T ---> Q being heat T ----> temperature, I have learned that in thermo when they refer at universe is just whatever is outside your system. so define your boundary and i think it's pretty simple.
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    How Do You Solve the Ice Cube and Spring Problem on a Slope?

    String Problem! Please Help! Homework Statement A 54 g ice cube can slide without friction up and down a 35 degree slope. The ice cube is pressed against a spring at the bottom of the slope, compressing the spring 12 cm. The spring constant is 27 N/m Homework Equations F = -kx F = ma...
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    Is the 1st Law of Thermodynamics different for engineers and physicists?

    so , let me get this straight ... in a situation where I have an ideal gas expanding: If U = Q + W, Work is negative If U = Q - W, Work is positive right!?
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    Is the 1st Law of Thermodynamics different for engineers and physicists?

    thanx guys, it is really hard to get a grip on this when i have to take two papers which include thermodynamics, and each of the teachers like to take on their own version of this... it makes it confusing... !
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    Troubleshooting Matlab Code: Tips and Tricks for Beginners

    Anyone Help Matlab! Please!? I am pretty bad at using matlab, i have never used it before and i don't know what's wrong with my code, i would honestly appreciate if someone could give me a hand. Script: x=linspace(0,5,10)'; y=[2.75 4.83 5.05 6.80 8.83 8.64 11.03 13.20 13.08 15.68]'...
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    How to Determine Temperature of Heat and Cold Reservoirs in a Carnot Cycle?

    yeah! got that one thank you very much! I thought about it straight away after posting it! thanx
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    How to Determine Temperature of Heat and Cold Reservoirs in a Carnot Cycle?

    Homework Statement All i want to know is how do i find the temperature of my heat and cold reservoir, given that they have a 90 degree celsius/kelvin differential and a 28% efficency. Homework Equations Efficency= Work out/ Work in = 1- Q out/Q in The Attempt at a Solution I been...
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    Is the 1st Law of Thermodynamics different for engineers and physicists?

    Hi to all! recently I been doing a lot of thermodynamics in University, however I have a huge problem. Because it is my first semester I have to take physics class for freshmen, however I also take at the same time physics for year 2 Uni students. (This is because I can, because I am already...
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    Solving Isothermal Process: Heat Supplied at Constant Pressure & Volume

    Homework Statement I have a diagram of a process of a monoatomic gas. and the problem is that I know that the total amount of work = total amount of heat, so there is no internal energy change. why? because my process started at the same temp that it finished. how ever... it is asking me...
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    Maxwell-Boltzman Distribution for Ideal Gases (Thermodynamics)

    yeah sorry i postulated wrong, here it is what i meant, 10^6 molecules are needed to establish a Maxwell-Boltzmann distribution, what is the minimum volume for the ideal gas law to hold @ 1atm and 0 C. The thing is that i didn't want to post the problem I really need to think it by myself i...
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    Maxwell-Boltzman Distribution for Ideal Gases (Thermodynamics)

    I just have a question of this subject, it is a pretty straight forward concept, however there are things that i just can;t figure out, like in any given gas which is the minimum volume required to have a maxwell boltzman distribution, @ 1 atm 273.15 K ? I honestly just can't figure it out...
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