For each of the scenarios below, determine how the total mass of the described object or system is changing, and say whether the scenario Increases the Mass, Decreases the Mass, or that the Mass Remains Unchanged:
A hot stone cooling down
A closed, thermally isolated box containing a controlled exothermic nuclearreaction
A closed, thermally isolated box containing a controlled exothermic chemicalreaction
A glass full of ice cubes melting
A compressed spring slowly relaxing
A car batter being charged
In: Physics
. Ice at −11.0 °C and steam at 146 °C are brought together at atmospheric pressure in a perfectly insulated container. After thermal equilibrium is reached, the liquid phase at 48.0 °C is present. Ignoring the container and the equilibrium vapor pressure of the liquid, find the ratio of the mass of steam to the mass of ice. The specific heat capacity of steam is 2020 J/(kg.C°).
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An ideal transformer has 50 turns in its primary (input) and 450 turns in its secondary (output). 10.0-V ac is connected to the primary (input). a) What is the voltage on the secondary (output)? b) What is the secondary (output) current if a 10.0- resistor is connected to the secondary (output)? c) What is the power supplied to the primary (input)?
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A bullet of mass 5.00 g is fired horizontally into a wooden block of mass 1.16 kg resting on a horizontal surface. The coefficient of kinetic friction between block and surface is 0.240. The bullet remains embedded in the block, which is observed to slide a distance 0.200 m along the surface before stopping.
Part A What was the initial speed of the bullet?
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9. How do we know whether or not global warming is caused by humans?
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From experiments in which a small experimental plot of forest is subjected to excess carbon, and the growth of the trees along with the temperature are then measured. |
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From experiments in which excess carbon is injected into a laboratory-created Earth-like atmosphere, and the resulting temperature is measured. |
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From computer calculations that "predict" 20th-century temperatures based on natural variations, then on human-caused variations, and then on a mix of natural and human variations; the actual historical measurements then show that only natural variations are important. |
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From computer calculations that "predict" 20th-century temperatures, based on natural variations, then on human-caused variations, and then on a mix of natural and human variations; the actual historical measurements then show the importance of human variations. |
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Actually, scientists have been unable to determine this. |
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1. A uniform magnetic field ? = 0 ? + 0 ? + 76.0 ? μT occurs in
the region ? ≥ 0. There is no magnetic field at ? < 0.
i) If an electron enters the field at the origin with velocity ? =
400 ? + 0 ? + 0 ? km s −1 determine its position, ? = ? ? + ? ? + ?
?, when it exits the field.
ii) If a proton enters the field at the origin with the same
velocity as the electron, describe how its motion in the field will
differ from that of the electron. No calculation is required.
(?? = 9.11 × 10−31 kg; ? = 1.6 × 10−19 C)
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How is the cosmic microwave background a logical conclusion from the idea of the Big Bang?
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A uniform film of TiO2, 1036 nm thick and having index of refraction 2.62, is spread uniformly over the surface of crown glass of refractive index 1.52. Light of wavelength 490 nm falls at normal incidence onto the film from air. You want to increase the thickness of this film so that the reflected light cancels.
a) What is the minimum thickness of TiO2 that you must add so the reflected light cancels as desired?
b) After you make the adjustment in part (a), what is the path difference between the light reflected off the top of the film and the light that cancels it after traveling through the film? Express your answer in nanometers.
c) Express your answer in wavelengths of the light in the TiO2 film.
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I need from 6 to 8 line
What is interoperability as used in the EHR and what is its importance?
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What is the change in the form of energy that is shown by the change in direction of the compass needle when an electric current is passed beneath it?
When the magnet is moved inside the coil of wire, what does the Galvinometer indicate?
Would making the fixed magnet stronger, have an effect on the amount of current produced?
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A 320 g block is dropped onto a relaxed vertical spring that has a spring constant of k = 1.8 N/cm (see the figure). The block becomes attached to the spring and compresses the spring 10 cm before momentarily stopping. While the spring is being compressed, what work is done on the block by (a) the gravitational force on it and (b) the spring force? (c) What is the speed of the block just before it hits the spring? (Assume that friction is negligible.) (d) If the speed at impact is doubled, what is the maximum compression of the spring?
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thermodynamics:
Explain why the properties of liquids can be estimated (with reasonable accuracy) as a function of temperature only
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The density of a 10 kg cube of silver is 10.5 g/cm3. What would the density of a 5 kg cube of silver be?
I thought the answer would be 5.25 g/cm^3 because m1/m2=p1/p2 so 10kg/5kg=10.5 g/cm^3/ x and you solve for x. But this is coming up as wrong and I don't know why, do i need to convert the kg to g???
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A 10.3 g wire has a density of 5.9 g/cm3 and a resistivity of 1.51 × 10−7 Ω · m . The wire has a resistance of 106 Ω . How long is the wire? The wire is made up of atoms with molecular mass 48 g/mol. What is the drift speed of the electrons when there is a voltage drop of 243.8 V across the wire? Assume there is one conduction electron per atom. The fundamental charge is 1.602 × 10−19 C. Answer in units of m/s.
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