photoelectric physics lab
Even though this experiment is mathematically simple, its
conceptual significance is immense. Explain how the experiment
confirms the quantized nature of photon energy. How is the
connection established between wave and particle theories of light?
How are we able to see that electrons in atoms exist in discrete
energy orbitals?
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A parallel plate capacitor with plate separation d is connected to a battery. The capacitor is fully charged to Q Coulombs and a voltage of V. (C is the capacitance and U is the stored energy.) Answer the following questions regarding the capacitor charged by a battery.
For each statement below, select True or False.
1. With the capacitor connected to the battery, increasing d increases U.
2. After being disconnected from the battery, inserting a dielectric with κ will decrease V.
3. With the capacitor connected to the battery, decreasing d decreases Q.
4. After being disconnected from the battery, inserting a dielectric with κ will increase U.
5. After being disconnected from the battery, inserting a dielectric with κ will decrease C.
6. After being disconnected from the battery, decreasing d increases C.
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A 8.0 V potential difference is applied between the ends of a 0.80 mm -diameter, 25 cm -long nichrome wire. What is the current in the wire?
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where does the formula v = sqr(2gh) come from (what formula is it a simplification of and how)
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Calculate the moment of inertia of the letter E rotating about its lower horizontal segment. In other words, the lower segment is the axis of rotation. The length of each horizontal segment is L, and the length of the vertical segment is 2L. The total mass of the system is M, and all segments have the same linear density. FYI, the moment of inertia of a thin rod about one end is 1/3 x mass x (length)2 .
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A 195 g block is pressed against a spring of force constant 1.60 kN/m until the block compresses the spring 10.0 cm. The spring rests at the bottom of a ramp inclined at 60.0° to the horizontal. Using energy considerations, determine how far up the incline (in m) the block moves from its initial position before it stops under the following conditions.
(a)
if the ramp exerts no friction force on the block
m
(b)
if the coefficient of kinetic friction is 0.360
m
(c)
What If? If the ramp is 4.00 m long, what is the maximum coefficient of friction that would allow the block to reach the end of the ramp?
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For a satellite at a height of 25,000 miles, at what speed must the satellite be traveling to achieve a circular orbit? (A score of 100% will tell you that you have achieved a circular orbit).
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Consider a microscopic springmass system (with a single spring and a single mass) whose spring stiffness is k = 50 N/m and mass is m = 4 × 10−26 kg. a. What is the smallest amount of vibrational energy that can be added to this system? b. In a collection of microscopic oscillators, the temperature is high enough that the ground state and the first three excited states are occupied. What are the possible energies and wavelengths of the photons emitted by the oscillators.
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2.4 g of helium at an initial temperature of 330 K interacts thermally with 9.0 g of oxygen at an initial temperature of 570 K .
a.) What is the initial thermal energy of each gas? Express your answer using two significant figures. Enter your answers numerically separated by a comma.
b.)What is the final thermal energy of each gas? Express your answer using two significant figures. Enter your answers numerically separated by a comma
c.) How much heat energy is transferred, and in which direction?
d.) From helium to oxygen or oxygen to helium?
e.)What is the final temperature? Express your answer using three significant figures and in Kelvin.
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What is the wavelength of the matter wave associated with a proton moving at 381381 m/s?
wavelength of proton matter wave:
What is the wavelength of the matter wave associated with a 153153 kg astronaut (including her spacesuit) moving at the same speed?
wavelength of astronaut matter wave:
What is the wavelength of the matter wave associated with Earth moving along its orbit around the Sun?
wavelength of Earth matter wave:
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How much energy could we get from flattening the Rocky Mountains? Guesstimate how much potential energy is stored in a mountain range.
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If 39.6 cm of copper wire (diameter = 0.872 mm, resistivity = 1.69
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A 40.0 kg child swings in a swing supported by two chains, each 3.00 m long. The tension is each chain at the lowest point is 350 N. Find (a) the child's speed at the lowest point and (b) the force exerted by the seat on the child at the lowest point. (Ignore the mass of the seat.)
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2. A cylinder is filled with helium gas at 323 K and 118 atmospheres. The volume of the cylinder is 3.07 liters. What is the total number of atoms in the gas?
3. One mole of helium gas at 297 K is allowed to expand slowly (isothermally) from an initial volume of 3.50 liters to a final volume of 16.1 liters. How much heat flows into the gas?
4. Helium gas is kept in a container surrounded by perfect vacuum p=0 (e.g. in space). The pressure inside the container is 288 Pa. Suddenly, the container breaks and the gas expands rapidly (i.e. adiabatically). What is the pressure of the gas when the volume has tripled?
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