Specific Definition and 1000 Threads

Homework Statement Were doing this lab that is related to finding the specific heat and heat of fusion of water. To put the lab simply we filled aluminum calorimeters with water that's around 35°C. After that we took a handful of ice and it into the calorimeter full of water and measured the...

I have an exam today, a final exam. Usually I don't ask this, but its an physics exam so I will need as much as help I could said. With that said, I was wondering if you had any specific tips on taking a physics exam? Like how to dissect a problem.

Homework Statement Let G be an Abelian group and let H+{x^3 : x is an element of G} Find a non-Abelian group in which H is not a subgroup Homework Equations I wish it was that easy... The Attempt at a Solution I looked at the quaternion group, and some other matrix groups, but...

When a 35 gram piece of some metal at 100°C is placed in water, it loses 775 calories of heat while cooling to 30°C. Calculate the specific heat capacity of this metal. Q = mc(DELTA)T T = 70 degrees C m = 35 g Q = 775 cal ?? When i plugged it in i got 0.34 but the program said it...

Homework Statement It takes 15 seconds to warm ice 15 degrees ( -15 degrees celsius to 0 degrees celsius). The ice has a mass of .25 kg. The energy is supplied at 530 W to the ice. Homework Equations Q = mc delta T The Attempt at a Solution I plugged in all the information for Q...

I have a question on finding a specific solution to Einstein's Field Equations. This is purely for my own curiosity. Suppose you were given this picture. How would you find the curvature of the point directly beneath the Earth in the picture, i.e. the point in which the space-time is...

Himiko has been in the news and I’d like to be sure I have the context of this correct. They can tell the light is 12.9 billion years old by how much it’s red shifted. That’s roughly 800 million years after the big bang. In that time, the universe has expanded by a factor of 8. If the light...

Finding potential at a specific point in the circuit... Help! Homework Statement ....... ground .......| ----R2------------------- |......|...| |......|...| |......|...| R1......R3...R4 |......|...| |......--------- |......| Emf1.....Emf2...

I understand that a beta plus decay emits positron and beta minus decay emits electron. For the calculation of kinetic energy of the particle released, you take into account the mass of electron for beta plus, but why is it that you DON'T take into account the mass of electron for beta minus? I...

can anyone explain the relationship between specific heat and thermal conductivity?

specific heat problem...simple, but I am missing something ? Homework Statement Trying to beat the heat of the last summer, a physics grad student went to the local toy store and purchased a plastic child's swimming pool. Upon returning home, he filled it with 200 liters of water at 25 C...

Homework Statement An ion of a magnesium isotope has A=24 and Z=12. Find the specific charge Homework Equations The Attempt at a Solution I know that the charge of a proton in Coulombs is 1.60\times10^{-19}. From the information given, I know that I have 12 protons and 24-12=12...

I have been wondering, does specific heat capacity affect the rate of heat flow from one substance to another? For example if the substances at heated up to the same temperature then left outside until thermal equilibrium is reached. I would think the one with the larger specific heat...

Homework Statement How much milk at 11 degrees Celcius was added to 0.16 kg of coffee at 91 degrees Celcius if the final temperature is 76.8 degrees Celcius? Homework Equations Well my teacher explained how to rearrange cm∆T = cm∆T to somehow come up with an equation to solve for the...

Homework Statement How much ice was added to a 0.75 kg jug of lemonade at 15 degrees celcius if the final temperature of the jug is 8 degrees celcius? (Assume the lemonade has the specific heat capacity of water.) Homework Equations Q = cm∆T The Attempt at a Solution Well I think I...

Homework Statement A piston-cylinder device contains 1.2kg Nitrogen gas at 120 kPa and 300K. The gas is now compresses slowly in a polytropic process during which PV^1.3 = constant. The process ends when the volume is reduced by one-half. Determine the entropy change of Nitrogen during this...

Hi, I want to know how I could produce a solution with a high specific heat, meaning it could store a huge amount of energy for each celsius degree raised. Im planing on using water as the solvent but I am having a hard time finding the right ions or molecules to make this solution able to...

im doing a calorimeter experiment and need to find the specific heat capacity of the calorimeter, but always gets a negative answer. Initial temp = 23 C Final temp = 60 C Change in temp = 37 C Mass of calorimeter = 0.027645kg Mass of water = 0.1kg Specific heat capacity water = 4200...

Homework Statement The specific heat of a substance varies with temperature according to: c = 0.20 + 0.14T + 0.023T^{2}, with T in deg-C and c in cal/gK. Find the energy required to raise the temperature of 2.0g of this substance from 5.0C to 15C. Homework Equations Q=mc\DeltaT K= C +...

I'm currently in my first year of university, and I have a couple options for my degree. I can: 1) Take a degree where you concentrate in two areas. You concentrate on one a little more than the other, but end up with a broad knowledge of both. 2) Do a degree in physics. 3) Do a degree...

I've been assigned the infamous egg drop project, and have been brainstorming as many ideas as possible. However, I have many restrictions, and the one I am having the most trouble with is size. My container cannot be any larger than 4"x4"x6", though it must protect the egg from a fall of...

I would like an explanation with this formulas for a rocket engine and any other engine to calculate its exhaust velocity and its specific impulse. I realized that this formulas neglect combustion temperature, engine pressure, speed of the fuel is injected, etc. -----------------------------...

Alright, so my current class assignment is to create a program that will read several accounts, whether or not its a savings, the amount in the acocunt, then make calculations for interest and fines based on that info. The setup for the input file is like this: account checking/savings amount...

Hey guys, doing some research here on Specific energy absorption of Aluminum 1016 T6 extrusion. 300mm length. I have to try and increase the SEA within this control volume. I have couple ideas, what do you think? I am going to apply a 150N load to the extrusion through compression and compare...

Hoping someone could double-check for me... Homework Statement 1) A 90 g block of unknown metal is heated to 86 degrees C and put in an insulated cup with 175 g water at 23 degrees C. At equilibrium, they are both 25.8 degrees C. What is the specific heat of the metal block? 2) A well...

if I am doing a reaction of acids and bases, do i just use the specific heat capacity of 4.18J, or is there a different one for different solutions?!?

Homework Statement Derive the Following Equations: c = [(m_w*c_w + m_c*c_al) (T_e - T_i)] / m_s*(T_s - T_e) and L = (m_w*c_w + m_c*c_al) * (T_i - T_e) - m_I*c_w * [(T_e- T_m)/m_I] Homework Equations T_i - initial temp of water and calorimeter T_m - melting temp of ice T_e -...

I've read that: specific heat capacity at constant pressure = dU-W / m. dT dU = change in internal energy W = work done m = mass of gas dT = change in temperature ----------------------------------- However, shouldn't the right hand side equate to specific heat capacity at...

I read that for an ideal gas, the specific enthalpy (h) at constant pressure is equal to the specific internal energy of the gas. How do I proof that? I know that: 1.) specific enthalpy = specific internal energy + pressure x specific volume 2.) Internal energy at constant pressure =...

Hi, I'm new to the technical aspects of astronomy and I'm having trouble quantifying what the definitions of some of these terms are. I can find equations that relate most of them, but I'm not sure how to use any of them. The terms are specific intensity, flux, flux density, and monochromatic...

There are lots of tables out there for finding the inverse laplace transform of: \frac{1}{(s+b)^{2}+a^{2}} or \frac{s}{(s+b)^{2}+a^{2}} but what if a^{2} is negative? I don't know what useful formula I should split it up into.

Homework Statement Let 25.2 J of heat be added to a particular ideal gas. As a result, its volume changes from 46.0 to 101.2 cm3 while the pressure remains constant at 1.0 atm. By how much did the internal energy of the gas change? 19.6 J is the answer which i understand how to get the...

An object with mass 30kg and specific gravity 3.6 is placed in a fluid whose specific gravity is 1.2. Neglecting viscosity, what is the objects acceleration and weight? I guessed on this one. Not sure how to make things come together. I said that a=2/3(g) and F=200N

I recall being taught that electrons in various "orbitals" or "energy states" absorb and emit photons of a specific frequency. I also learned that relative speed changes the observed wavelength of photons, due to the Doppler Effect. So, how is it that some electron can "absorb" a photon of a...

specific heat of combustion?? help Homework Statement Chemical Properties of gasoline components Using C5 to C10 hydrocarbons, conduct an experiment to determine the effect of one property of the hydrocarbon on the specific heat of combustion. Homework Equations The Attempt at a...

Hi, everyone Since specific Volume is 1/density, How come this web can provide a decreasing Specific Volume of Air when the temperature increase? http://www.engineeringtoolbox.com/air-properties-d_1257.html Thanks for your help.

It's a common observation that sometimes the slightest occurrances are remebered by us for entires lives while we forget relatively important things quite soon. Why is this so? Why can't we remember other things just like these trivial things? Is our brain working at some extraordinary...

Homework Statement Several small piece of aluminum, having total (combined) mass of 2.5 kg are placed in liquid nitrogen and, when removed, are at a temperature of -135C. The aluminum is transferred to an insulating container with 0.50 kg of water. The water is at 25.0C [ Ignore heat lost from...

Homework Statement I must find temperature at each state, for starters. This is a Diesel cycle with a non-isentropic compression process, but standard the rest of the way. The specific heat is variable with temperature. Fluid is air Givens: compression efficiency (\eta_{c}), initial...

Homework Statement The diagram below shows a one-dimensional row of 5 microscopic objects each of mass 410-26 kg, connected by forces that can be modeled by springs of stiffness 26 N/m (so each object can be modeled as if it were connected to a single spring of effective stiffness 4ks = 104 N/m...

I have an alloy and found the average specific heat of the metal to be 289 J/kg°C. I need to know what type of metal it is. I've looked at several different tables of specific heats, but can't find what I'm looking for. Can anyone help me?

Homework Statement Aluminium-Lithium alloys have been developed by the aircraft industry to reduce the weight and improve the performance of its aircraft. A commercial aircraft skin material having a density of 2.47 g/cm3 is desired. Compute the concentration of Li (in wt%) that is required...

Homework Statement a 4kg iron hammer is initally 700 degree celcius is droppped into a bucket containing 20kg of water at 25degree celcius. what is the final temperture Homework Equations q=mc(delta)T The Attempt at a Solution m1=4kg m2=20kg T1=700=973K T2=25=298 i know...

This is a really simple problem, but I just can't remember how to combine the container and the water. Homework Statement An aluminum container weighing 200g contains 500g of water at 20*c. A 300g shot of the same aluminum at 100*c is put into the water. The specific heat for the aluminum...

Does anyone know where I might be able to find the specific heat capacity of steel (in English units)? Thank you!

Specific Heat-- please help! Homework Statement A piece of copper of mass 0.5 kg is heated to 610 degrees celcius and then dropped into a copper calorimeter of mass 0.11 kg containing 0.13 kg of water at 21 degrees celcius. If the specific heat of copper is 390 J/Kg/K, calculate the mass of...

I want to calculate the reaction heat in a ammonia convertor but I need some specific heats of N2,NH3,Ar and CH4 at 500°C and 200bar. I could find data at 500°C but not at that pressure. thanks Stefaan

Homework Statement An aluminum cylinder weighs 1.03 N. When this same cylinder is completely submerged in alcohol, the volume of the displaced alcohol is 3.89 multiplied by 10-5 m3. If the cylinder is suspended from a scale while submerged in the alcohol, the scale reading is 0.732 N. What...

Homework Statement An ice tray containing 200 g of water at 25 degrees celecius is placed in the freezer. How much heat energy has to be removed to change the water into ice at -4 degrees celcius? Homework Equations Q= mc(Tf-Ti) + MLf + mc(Tf-Ti) The Attempt at a Solution I know...

I was reading a lab online and I came across one that dealt with Specific Gravity and Buoyany and stuff.. and then they had these equations: *Note: p = density, M = mass, V = Volume, g = gravitational acceleration, W = Weight Subscripts: S = substance, W = water SG = pS / sW = (MS / VS)...