 # Get help with physics questions

Recent questions in Physics Jayla Faulkner 2022-04-06

### Is Planck temperature really the highest temperature?Actually I was learning about Wien's displacement law. It states that$\lambda T=2.898×{10}^{-3}mK$This is actually a part of Planck's law where the Planck's constant originated.Now Planck's temperature is given as${T}_{p}=\sqrt{\frac{h{c}^{5}}{2\pi G{k}_{b}^{2}}}=1.416×{10}^{32}K$Now Planck's length is $1.616×{10}^{-35}m$Now since the smallest possible wavelength is Planck's length, we can say wavelength of the electromagnetic radiation is Planck's length (Assume the energy doesn't create a black hole).Now according to Wien's displacement law,${l}_{p}T=2.898×{10}^{-3}mK$Now solving this we get $1.79×{10}^{32}K$, which is higher than the actual Planck's temperature.Since this displacement law is completely derived from Planck's law, it bit frustrated me. I'm a bit confused. Is it the limit of the displacement law or my flaw?Please rectify this.(Sorry if I made any mistake. I'm new to this one. Please explain my mistake. I'm glad to hear that.) Dennis Montoya 2022-04-06

### What is the half life of Uranium 234? Adelyn Rodriguez 2022-04-06

### If an observer were to rotate around a point at near light speeds, what sort of length contraction would he observe the universe undergo? quiquenobi2v6 2021-12-15

### An open tank has a vertical partition and on one side contains gasoline with a density $p=700\frac{kg}{{m}^{3}}$ at a depth of 4m. Arectangular gate that is 4 m high and 2 m wide and hinged at one end is located in the partition. Water is slowly added to the empty side of the tank. At what depth, h, will the gate start to open? alka8q7 2021-11-17

### The air in a bicycle tire is bubbled through water and collected at ${25}^{\circ }C$. If the total volume of gas collected is 5.45 L at a temperature of ${25}^{\circ }C$ and a pressure of 745 torr, how many moles of gas were in the bicycle tire? rastafarral6 2021-11-14

### 10 kg of R-134a at 300 kPa fills a rigid container whose volume is 14 L. Determine the temperature and total enthalpy in the container. The container is now heated until the pressure is 600 kPa. Determine the temperature and total enthalpy when the heating is completed. Nannie Mack 2021-05-04

### When a gas is taken from a to c along the curved path in the figure (Figure 1) , the work done by the gas is W = -40 J and the heat added to the gas is Q = -140 J . Along path abc, the work done by the gas is W = -50 J . (That is, 50 J of work is done on the gas.) I keep on missing Part D. The answer for part D is not -150,150,-155,108,105( was close but it said not quite check calculations) Part A What is Q for path abc? Express your answer to two significant figures and include the appropriate units. Part B f Pc=1/2Pb, what is W for path cda? Express your answer to two significant figures and include the appropriate units. Part C What is Q for path cda? Express your answer to two significant figures and include the appropriate units. Part D What is Ua?Uc? Express your answer to two significant figures and include the appropriate units. Part E If Ud?Uc=42J, what is Q for path da? Express your answer to two significant figures and include the appropriate units. Falak Kinney 2021-04-06

### Part A Suppose a uniform slender rod has length L and mass m. The moment of inertia of the rod about about an axis that is perpendicular to the rod and that  Cheyanne Leigh 2021-04-04

### Water at a pressure of $3.00×{10}^{5}$ Pa flows through a horizontal pipe at a speed of 1.00 m/s. the pipe narrows to 1/4 its original diameter. Find the following: A. The flow speed in the narrow section B. the pressure in the narrow section smileycellist2 2021-03-23

### A 45-g piece of ice at 0 degree C is added to a sample of water at 8 degrees C. All of the ice melts and the temperature of the water decreases to 0 degree C. How many grams of water were there in the sample? preprekomW 2021-01-13

### An ice cube tray of negligible mass contains 0.315 kg of water at ${17.7}^{\circ }$. How much heat must be removed to cool the water to ${0.0}^{\circ }$ and freeze it? beljuA 2021-01-13

### A cubic block of wood, 10.0 cm on each side, floats at the interface between oil and water with is lower surface 1.50 cm below the interface. The density of oil is 790 kg/m(cubic). a) what is the gauge pressure on the upper surface of the block? b) what is the gauge pressure on the lower surface of the block? c) what is the mass and density of the block? Anish Buchanan 2020-12-30

### A majorette in a parade is performing some acrobatic twirlingsof her baton. Assume that the baton is a uniform rod of mass 0.120 kg and length 80.0 cm. With a skillful move, the majorette changes the rotation ofher baton so that now it is spinning about an axis passing throughits end at the same angular velocity 3.00 rad/s as before. What is the new angularmomentum of the rod? York 2020-11-09
### A 0.30kg softball has a velocity of 15m/s at anangle of 35 degree below the horizontal just before making contactwith the bat. What is the magnitude of the change in momentum ofthe ball while it is in contact with the bat if the ball leaves thebat with a velocity of (a) 20m/s, velocity downward, and (b) 20m/s, horizontally back toward the pitcher? a) $\pi =0.3kg\left(-15\frac{m}{s}\right)\mathrm{cos}\left(35\right)i$ b) $\pi =0.3\cdot 20\frac{m}{s}=6\frac{m}{s}$ Ive Tammy Todd 2020-10-18