Degrees Definition and 656 Threads

Hi I am planning on building an immersion heater to heat oil when it is -20 C degrees outside. I need some help calculating the heat transfer. I want to find out how long it would take to heat around 10 litres of oil from -20 degrees to 10 degrees using an immersion heater with a constant...

So I'm working on my bachelor's right now, junior at UC Berkeley. I've been wondering if people could share their experiences in completing their degrees without any further math (past differentials, linear, multi variable calc.). I know more math isn't required, and I've been under the...

I have been accepted to the UT Austin Cockrell School of Engineering for Mechanical Engineering in Fall 2017. I'll be starting as a sophomore because I have finished all my general education requirements. However, I am not entirely sure I want to stick to MechE. I have been considering Chemical...

Hi, I'm trying to build a motorized rotating platform, and was wondering what drive system to choose. The platform is 1.2 meters in diameter with two cylindrical objects (max 25 kg each) attached on top - total weight to rotate approx 80 kg. I want the platform to be programmed to...

Homework Statement A problem of practical interest is to make a beam of electrons turn a 90∘ corner. This can be done with the parallel-plate capacitor shown in the figure (Figure 1) . An electron with kinetic energy 2.0×10−17 J enters through a small hole in the bottom plate of the capacitor...

Thread for context this question came up in: http://ecomodder.com/forum/showthread.php/how-improve-fuel-economy-tonneau-cover-124-6.html#post535358 I'm guessing we will want the answer in pounds, perhaps FT/Pounds. Ballpark numbers on horizontal, vertical and or down-force and or lift. Just...

Hi all, I'm trying to find a special refrigeration device that can goes from -40 Degrees to 70 degrees. I need this machine for a laboratory to test sensors in differente temperatures. Does anyone knows where can I find something like that? Kind Regards Vicente

Eventually the Sun will go through its phases and cool down. Is it possible to calculate how long it will take for the surface to cool to 75 degrees Fahrenheit?

Im teaching math and one of my students asked me something about trigonometry. Say you are to generally solve: sin(x + 1) = 0.5 And that's all the information you are given. How would you know to solve for radians or degrees?

I am a little confused as to why my book is saying that the potential energy of a dipole is 0 at 90 degrees relative to the electric field lines. When it has the stored energy to turn from 90deg to 0deg if no force is acting on it. Wouldn't it make sense to use 0deg as a reference point then?

Homework Statement The formula for centripetal acceleration (Ac) is $$Ac = \frac {4π^2r} {T^2},$$ where r = radius and T = period of rotation Homework Equations The above formula can be rearranged as follows: $$Ac = \frac {2π} {T} × \frac {2π} {T} × \frac {r} {1},$$ $$= \frac {2π} {T} × \frac...

I have a bachelors degree in physics and I want to receive an MS before I move on to a PhD. I don't think I' ready to commit the time and effort to a Doctorate, but I do want to live abroad and study physics for a Masters. I would like to do it outside the US, but I would settle for a domestic...

Hi All, I have just found in the internet an identity showing that the Golden Ratio can be expressed as a function of the cosine of the angle of 36 degrees. It seemed to me as an important fact related to this specific angle. Had this fact, historically, any relevance to the choice of the 360...

Hello. I'm feeling a little bit depressed, desperate and excited, because I am graduating in May of next year. I will have a BS in chemistry, a BS in physics and a minor in biochemistry. What I am wondering is, what kind of job can I hope for with these degrees? I've done research work in an...

For personal reasons, I am moving to an area where there are not any larger universities that offer Master's and PhD programs, and I am also not 100% sure I want to currently pursue a PhD or not. One route that I am thinking of taking, though, is to find a job in order to see what industry is...

I was approximating tan46 using derivatives. If I do it using radians, then we know the value of the function at pi/4, and the difference, i.e. dx is 1 degree=0.01745 radians. It's derivative at x=pi/4 is 2. So, approximate change in the value of the function is= 2*0.01745 ...

A photon has a spin of 1, while an electron is 1/2. I've heard it said that the electron needs to spin 720 degrees to complete a full cycle. Is there any proof that the electron is spinning 720 degrees and not just spinning 360 degrees, but at a lower harmonic of the photon-- 1/2 the photon's...

Dear friends. I am a cardiovascular health researcher writing on behalf of my research team based in Copenhagen, Denmark. We plan to conduct a high-altitude field study on cardiopulmonary function assesed by ultrasound on Aconcagua summit in near 7000 meters altitude. Reports say it will be...

Homework Statement A source of sound frequency 550 Hz emits waves of wavelength 600 mm in air at 20 °C. What is the velocity of sound in air at this temperature? What would be the wavelength of the sound from this source in air at 0 °C? Answers: 330 m s-1, 579 mm 2. The attempt at a solution...

Homework Statement How many degrees of freedom does water vapor have Homework Equations Translational up to 3 rotational up to 3 Vibration up to 6 The Attempt at a Solution Well I said water vapor had 3 translational. It can move along the x, y, or z axis I said it had 2 rotational (the...

The EM wave and the photon have two degrees of freedom. Their polarization directions and spin states, respectively. But they move in space, too. I mean light has the freedom to go in all directions in space. Like a macroscopic ball in 3-D space, which can go all three directions, if there are...

Homework Statement A small bead is threaded on a smooth circular wire of radius r which is fixed in a vertical plane. The bead is projected from the lowest point of the wire with speed √6gr. FInd the speed of the bead when it has turned through: (a) 60°, (b) 90°, (c) 180°, (d) 300°. Answers...

Hi I have been dealing with a fluid mechanics pressure gradient problem and from a statistical view point I can see how it resolves itself but am puzzled as to how it can occur at the molecular scale from a conservation of linear momentum perspective if Momentum is a conserved quantity While...

Hello! I was hoping someone here could help me solve a real world problem. So my university pool has something called a bulkhead, which is basically a bridge that floats above the water so that people can walk across the shorter dimension of the rectangular pool (50 meters long, 25 yards wide)...

Homework Statement A three-dimensional harmonic oscillator is in thermal equilibrium with a temperature reservoir at temperature T. The average total energy of oscillator is A. ½kT B. kT C. ³⁄₂kT D. 3kT E. 6kT Homework Equations Equipartition theorem The Attempt at a Solution So I know the...

A minha pergunta é na divisão 10800/1110 My question is in the division 10800/1110 ?

A 10 Kg block lies on a smooth plane inclined at 51 degrees. What force parallel to the incline would prevent the block from slipping?

Question: what is the smallest positive real number x with the property that the sine of x degrees is equal to the sine of x radian? My try: 0. But zero isn't a positive number. How do I even begin to solve it? I tried taking inverse on both sides of sin(theta)=sin(x), but that didn't help.

Does anyone know if there is any internationally agreed method for determining where zero degrees longitude is when mapping other planets etc.?

So this upcoming fall I'm beginning college and decided to pursue a BS in Physics. Although I'm not exactly sure what field I want to pursue in physics, I think I want go into quantum mechanics after I graduate and obtain my PhD. Although I love chemistry, it's not what I want to do as a career...

Im doing a proof. For instance all sums of a triangle add upp to 180 degrees. But how to i motivate that all arcs on a circle add up to 360 degrees. A part of my proof is that Arc A + B + C = 360 degrees. But i don't know what to write in the column that motivates every step. ! Like a lap is...

I understand the molecular principles behind the reflection itself, however it presents many problems, such as the one above. If you could explain it as easily as you can, I would be grateful. :)

I know that water is the most dense at 4 degrees celsius. That's why water at the bottom of a sea has that temperature. But how did it get that temperatur in the first place and why does the energy not distribute itself in such a way that the temperature is the same throught? Is it the particles...

Ohio's state government is contemplating allowing community colleges (CC) to offer baccalaureate degree programs: https://www.insidehighered.com/news/2015/02/02/ohios-two-year-colleges-may-soon-offer-bachelors-degrees-and-access-state-aid Crucially, CC may not increase credit hour tuition for...

Hello everyone! I recently read some information about the equipartition theorem and degrees of freedom in thermodinamics. I read that for the linear N-atomic and non-linear N-atomic molecules in order to allow the vibrational degrees of freedom to appear we need a really high temperature. I...

I just found out V = Acos(wt+phi) is made up of both radians and degrees, where w is rad/s and phi is degree. You have to convert either one to the other to calculate it. Assume phi is 0 degrees. I(t) = Icos(wt), and w is radian/s. So then capacitor impedance is -j/wC. V(t) = (I<0) *...

Dear PF Forum, As we know in polynomial 2 degrees AX2 + BX + C = 0, there's a formula for solving it. What about 3 degrees for example: AX3 + BX2 + CX + D = 0, there's is really no formula for solving it? The only way to solve it is by hand? I have several methods in my head, at least...

Homework Statement The resistance of a bobbinin 0 grades celcius is 3.35 ohm. What is its resistance in 50 grades celcius? thermal constant=0.0037 Homework Equations R1=R0[1+alpha(t-t0)] The Attempt at a Solution Using this formula R1=3.35[1+0.0037(50-0)]=3.35*1.185=3.96975, but the answer in...

Recently, Germany broke headlines when they fired up their nuclear fusion reactor. As I'm sure most everyone on this forum knows this, they plan on creating fusion by heating plasma to absurd temperatures while containing it in a magnetic field. What method do they use to heat the gas and...

Homework Statement A Train is driving with a uniformed velocity. v=1/4 c. The train is driving under a bridge, which is rotated \theta=30 degree in relation to the railway. The bridges length is 20 m long in a reference frame of the bridge (stationary bridge). Calculate the length of the...

Homework Statement Point transformation in a system with 2 degrees of freedom is: $$Q_1=q_1^2\\Q_2=q_q+q_2$$ a) find the most general $P_1$ and $P_2$ such that overall transformation is canonical b) Show that for some $P_1$ and $P_2$ the hamiltonain...

Not a textbook/homework problem so I'm not using the format (hopefully that's ok). Can someone offer an explanation of normal modes and how to calculate the degrees of freedom in a system of coupled oscillators? From what I've seen the degrees of freedom seems to be equal to the number of...

Edit: this thread was split off from another where it was off topic https://www.physicsforums.com/threads/could-it-be-meaningful-to-speak-of-the-density-of-space.843442/ . The question in the original thread was if you could express GR in terms of a density of spacetime. I made a mistake in the...

Hello, I am about to complete my BSc in Physics and I'd like to pursue a MSc in a field related to Climate or Environmental Physics. I'd like it to be a mainly experimental curriculum with a decent amount of simulation/data analysis and to be in a country with none to low fees for EU students...

Because a triangle comes out to 180 degrees, and yet it can only have three sides. A circle has 360 degrees, but its number of "sides" are uncountable. Can someone explain this?

Hey! How can I delay a sinusodial signal (voltage) 90 or 180 degrees? I have been thinking of a capacitor or an inductor in parallel with the voltage source but these components do not impact the phaseshift of the voltage but the current. Can anyone help me please? EDIT: I know that there are...

Homework Statement A thin rod, 0.79 m long, is pivoted such that it hangs vertically from one end. You want to hit the free end of the rod just hard enough to get the rod to swing all the way up and over the pivot. How fast do you have to make the end go? Homework Equations P(change in...

Why exactly do electrical engineers represent sinusoidal signals with the frequency in terms of radians/sec but phase shift in terms of degrees? Why don't we represent the phase shift in radians? I'm curious where/why this convention originated.

The internet is really nebulous sometimes, I was looking and couldn't find the answer. I know that the line voltage is √3*Vphase<30degrees for a WYE. and that line current = √3*Iphase for a delta connection. But is that line current 30 degrees out of phase to the phase current? As the voltage...

When a degree of freedom exists, the object is considered free to move in this direction, so that it is not possible to transmit a force onto the object in this direction (i.e. the object slips away when push against, like on ice or ball bearings). For the object to react to a force through the...