3. Frequency and wavelength are both in your equation for speed. Why is it that, when you changed the frequency, you did not change the speed of the wave?
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Federal funding agencies must form committees to decide which telescope projects will receive funds for construction. When deciding whic projects wil be funded, the committees must consider:
that certain wavelengths of light are blocked from reaching Earth's surface by the atmosphere,
how efficiently telescopes work at different wavlengths, and
that telescopes in space are much more expensive to construct than Earth-based telescopes.
Using these three criteria, consider each pairing of telescope proposals listed below. For each pair, state which of the two you would choose to fund and explain your reasoning.
Pair A)
Project Beta: An X-ray wavelength telescope, located near the North Pole, which will be used to examine the Sun.
Project Alpha: An infrared wavelength telescope, placed on a satellite in orbit around Earth, which will be used to view supernovae.
Pair B)
Project Rho: A UV wavelength telescope, placed high atop Mauna Kea in Hawaii at 14,000 ft above sea level, which will be used to look at distant galaxies.
Project Sigma: A visible wavelength telescope, placed on a satellite orbit around Earth, which will be used to observe a pair of binary stars located in the constellation Ursa Major.
Pair C)
Project Zeta: A radio wavelength telescope, placed on the floor of the Mojave Desert, which will be used to detect potential communications from distant civilizations outside our solar system.
Project Epsilon: An infrared wavelength telescope, located in the high-elevation mountains of Chile, which will be used to view newly forming stars (protostars) in the Orion nebula.
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Hockey puck B rests on a smooth ice surface and is struck by a second puck A, which has the same mass. Puck A is initially traveling at 16.0m/s and is deflected 22.0 degrees from its initial direction. Assume that the collision is perfectly elastic.
a) Find the final speed of puck b after the collision.
b) Find the final speed of puck a after the collision.
c) Find the direction of b's velocity after the collision
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1. On a planet where the gravitational acceleration is g=10 m/s², a solid cube of wood measuring one foot on each edge exerts a uniform pressure of 3048 Pa on a flat tabletop due to its weight. Find the wood's specific gravity and state whether it will float on water. One foot is 0.3048 m.
2. A crown is made of an alloy consisting of gold (19 g/cc) and copper (9 g/cc). It weights 35 N in air, and 32.5 N when submerged in water. What fraction of its volume is gold?
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Discuss Einstein and Planck's collaborative work on the photoelectric effect and their differing views about whether science research is removed from social and political forces.
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The rotor in a certain electric motor is a flat, rectangular coil with 89 turns of wire and dimensions 2.57 cm by 4.20 cm. The rotor rotates in a uniform magnetic field of 0.800 T. When the plane of the rotor is perpendicular to the direction of the magnetic field, the rotor carries a current of 10.6 mA. In this orientation, the magnetic moment of the rotor is directed opposite the magnetic field. The rotor then turns through one-half revolution. This process is repeated to cause the rotor to turn steadily at an angular speed of 3.72 103 rev/min.
(a) Find the maximum torque acting on the rotor.
0.000815N
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A lens has a power of -1.72 D. You look through it a 1.00-cm long leaf held 33.34 cm from the lens. Calculate the image height, hi, in cm, including the correct sign (+ for upright, - for inverted).
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A WCU student, who is snowboarding at Cataloochee, slides horizontally off the ledge of snowbank that is 1.25 meters above the ground. When she leaves the ledge, she is initially moving horizontally at 7.50 m/s. Ignore air friction, as usual.
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1 point) A truck starts from rest and accelerates at 1?/?2 . 6 s later, a car accelerates from rest at the same starting point with an acceleration of 2.7m/s2 .
a) Where and when does the car catch the truck?
m from the starting point
at seconds from the moment the truck started to accelerate.
b) What are their velocities when they meet?
The truck : m/s
The car : m/s
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explain in simple terms the postulates of the special theory of relativity
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A 7.0-kg rock at a temperature of 30°C is dropped into a shallow lake at 30°C from a height of 1.0×10^5 m. What is the resulting change in entropy of the universe? (b) If the temperature of the rock is 100°C when it is dropped, what is the change of entropy of the universe? Assume that air friction is negligible (not a good assumption) and that c=860J/kg·K is the specific heat of the rock.
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A certain refrigerator has a COP of 5.00. When the refrigerator is running, its power input is 500 W. A sample of water of mass 500 g and temperature 20.0 ºC is placed in the freezer compartment. How long does it take to freeze the water to ice at 0ºC?ANS = 83.3 s
I can't seem to get 83.3s
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True or False
Determine if the following statements are true or false.
_____ 1. A liquid takes the volume of its container.
_____ 2. Particles of amorphous solids have no definite pattern.
_____ 3. A beef steak is an example of a crystalline solid.
_____ 4. Viscosity causes water to curve upward at the top rim of a glass.
_____ 5. There is more gas than any other state of matter in the universe.
_____ 6. All states of matter have a fixed mass and fixed volume.
_____ 7. The volume and shape of a solid can never change.
_____ 8. Surface tension explains why water forms droplets.
_____ 9. Water has greater viscosity than any other liquid.
_____ 10. A gas spreads out to fill all available space.
Matching
Match each definition with the correct term.
|
Definitions |
Terms |
|
_____ 1. state of matter that lacks a fixed volume and a fixed shape |
a. solid |
|
_____ 2. state of matter with a fixed volume and a fixed shape |
b. liquid |
|
_____ 3. energy that moves matter |
c. gas |
|
_____ 4. ability to cause changes in matter |
e. kinetic energy |
|
_____ 5. state of matter with a fixed volume but not a fixed shape |
f. state of matter |
|
_____ 6. state of matter that consists of ions |
g. energy |
|
_____ 7. solid, liquid, gas |
a. solid |
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A 4.9-m-wide swimming pool is filled to the top. The bottom of the pool becomes completely shaded in the afternoon when the sun is 22 ∘ above the horizon.
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