True or False , explain why
Light travels faster in vacuum than it does in a
glass.
When light enters a medium with a higher index of refraction, the ray is bent farther away from the line normal to the boundary.
The path of a ray of light between two points is the path that minimizes the travel time.
White light that is reflected from a surface will be separated into a visible spectrum.
If one stands by a swimming pool, a person standing in the pool will seem to have long legs.
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The cosmic microwave background (CMB) matches a 2.7 K blackbody spectrum extremely well. For a space telescope observing the CMB with an efficient detector with a collecting area of 0.01 m2, estimate (i) the wavelength at which the CMB peaks in intensity, (ii) the power in watts of CMB photons collected by the detector and (iii) the number of CMB photons per unit volume in the vicinity of the space telescope.
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A woman can read the large print in a newspaper only when it is at a distance of 62 cm or more from her eyes. (a) Is she nearsighted (myopic) or farsighted (hyperopic), and what kind of lens is used in her glasses to correct her eyesight? (b) What should be the refractive power (in diopters) of her glasses (worn 2.9 cm from the eyes), so she can read the newspaper at a distance of 29 cm from the eyes?
A: I know she's farsighted
B: I did (1/ 29-2.9 + 1/(62-2.9) = .05523 x 100 = 5.52 cm, which was wrong. How do I solve this part of the equation?
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3. A ski jumper starts from the top of a frictionless track making a 60° angle with the ground. The starting point is 25.0-m above the ground, and the jumper is launched from the upturned end of the track 3.00-m above the ground at an angle of 60°.
a) What is her speed as she leaves the jump?
b) How far away from the track does the jumper land?
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at the same diameter, an air bubble rises faster in liquid faster than a sand pebble falls in liquid water. The densities of air water and sand are 1.2,1000,2500 kg/M3 respectively.
Answer True of False whether or not the air buble travels faster. Need help don't understand the theory behind this question
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The discovery of the constant speed of light proved that classical physics was unable to explain more advanced scientific concepts and led to the birth of a new field—modern physics. The Michelson-Morley experiment proved that light moves at a constant speed at all times, regardless of the relative speed of the observer. Discuss why this characteristic makes light unique compared to all other moving objects in the universe. Support your reasoning with at least two concrete examples of other moving object
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What wavelength monochromatic source in the visible region (390 to 710 nm) can be used to constructively reflect off a soap film (n = 1.46) if the film is 77 nm thick?
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Two stars 19 light-years away are barely resolved by a 63 cm (mirror diameter) telescope. 1ly=9.461×1015m.How far apart are the stars? Assume λ = 550 nm and that the resolution is limited by diffraction.
d=_____? m
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A lens system consists of two lenses 14.0 cm
apart. The first lens is convex (converging) and has a focal length
of 6.72 cm. An object is placed 3.29 cm in front
of the first lens and produces an image 7.00 cm behind the
second lens.
Q1:What is the focal length of the second
lens?
A:5.215 cm
Q2:What is the magnification of the final image?
A2:
Please provide A2 and show all work, I already have the correct answer to Q1(5.215cm)
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Why do some gradients change frequencu while others change phase in MRI?
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An optical interferometer can detect a displacement of 0.1?, or ?50nm.
At what speed would a 3.0m stick "shrink" by 50 nm? Hint: Use the binomial approximation.
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8.0 x 10^15 electrons flow through a cross section of silver wire in 340 us with a drift speed of 7.6 x 10^-4m/s .
What is the diameter of the wire?
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Please answer it well.
TRUE or False: Beyound the point of stall, the wing generates zero lift and the airplane falls from the sky.
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An electron collides elastically with a stationary hydrogen atom. The mass of the hydrogen atom is 1837 times that of the electron. Assume that all motion, before and after the collision, occurs along the same straight line. What is the ratio of the kinetic energy of the hydrogen atom after the collision to that of the electron before the collision?
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Sketch a PV diagram and find the work done by the gas during the following stages. (Draw the PV diagram on paper. Your instructor may ask you to turn in this work.)
(a) A gas is expanded from a volume of 1.0 L to 2.6 L at a
constant pressure of 3.1 atm.
J
(b) The gas is then cooled at constant volume until the pressure
falls to 1.8 atm.
J
(c) The gas is then compressed at a constant pressure of 1.8 atm
from a volume of 2.6 L to 1.0 L. [Note: Be careful of the
signs.]
J
(d) The gas is heated until its pressure increases from 1.8 atm to
3.1 atm at a constant volume.
J
(e) Find the net work done during the complete cycle.
J
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