LASER IN DERMATOLOGY write effect,application,advantage and disadvantages of laser in dermatology and Referances
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A projectile is launched with an initial speed of 45.0 m/s at an angle of 40.0° above the horizontal. The projectile lands on a hillside 3.25 s later. Neglect air friction. (Assume that the +xaxis is to the right and the +yaxis is up along the page.)
(a) What is the projectile's velocity at the highest point of its trajectory?
magnitude  ? m/s 
direction ?  ° counterclockwise from the +xaxis 
(b) What is the straightline distance from where the projectile
was launched to where it hits its target?
? m
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In: Physics
Explain the difference between Fero and Paramagnatism
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Why are light bulbs in New Year's Christmas trees
usually switched on sequentially?
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CH 9 ITEM 11
A frictionless pulley has the shape of a uniform solid disk of mass 2.90 kg and radius 10 cm. A 1.70 kg stone is attached to a very light wire that is wrapped around the rim of the pulley, and the system is released from rest.
Part A
How far must the stone fall so that the pulley has 3.00 J of kinetic energy?
Part B
What percent of the total kinetic energy does the pulley have?
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Do standing waves explain why electron orbitals are quantized?
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Consider an RLC circuit that is driven by an AC source with an adjustable frequency. Is possible for the maximum voltage drop across the capacitor to exceed the maximum voltage? Explain in 100 words or less.
I know the answer is yes, but can you explain this conceptually, not mathmatically? thanks.
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In: Physics
A circular coil of 144 turns has a radius of 1.54 cm. (a) Calculate the current that results in a magnetic dipole moment of magnitude 2.13 A
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A ball is hit east from a 10 meter elevated platform with an initial velocity of <50, 0, 30> m/s. A wind blowing to the south produces an acceleration on the ball of 1.2 m/s^2.
a. Find the velocity and position vectors for t ≥0.
b. Determine the time of flight and range of the ball.
c. Determine the maximum height.
d. If you want the ball to land due east of your initial position, determine the correction
angle.
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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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The viscosity of SAE 10 motor oil at room temperature is about 0.25Pas. Consider a 5cm thick oil layer between two 5m2 surfaces.
a) Calculate the force on the bottom layer if the top later is moving at a constant speed of
3.5m/s.
b) If the force were to remain constant, how long will it take until the two layers are moving at the same speed?
c) Of course the problem is not that simple, explain what happen with the force and speed as
time passes.
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Hey, need answers to the following physics questions
7. A tiny ball (mass = 0.079 kg) carries a charge of 17.9 µC. What electric field (magnitude and direction) is needed to cause the ball to float above the ground??
8. A small object has a mass of 3.1 10^{3} kg and a charge of 32 µC. It is placed at a certain spot where there is an electric field. When released, the object experiences an acceleration of 2.31 10^{3} m/s^{2} in the direction of the +x axis. Determine the magnitude and direction of the electric field.
9. Four point charges have the same magnitude of 2.32 10^{12} C and are fixed to the corners of a square that is 4.10 cm on a side. Three of the charges are positive and one is negative. Determine the magnitude of the net electric field that exists at the center of the square.
10. A long, thin rod (length = 3.8 m) lies along the x axis, with its midpoint at the origin. In a vacuum, a +7.3 µC point charge is fixed to one end of the rod, and a 7.3 µC point charge is fixed to the other end. Everywhere in the x, y plane there is a constant external electric field (magnitude = 5.45 10^{3} N/C) that is perpendicular to the rod. With respect to the z axis, find the magnitude of the net torque applied to the rod.
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An ideal gas with γ=1.4 occupies 3.0 L at 300 K and 120 kPa pressure and is compressed adiabatically until its volume is 2.0 L. It's then cooled at constant pressure until it reaches 300 K, then allowed to expand isothermally back to state A.
Part A
Find the net work done on the gas.
Express your answer using two significant figures.


W = 
Part B
Find the minimum volume reached.
Express your answer using two significant figures.


Vmin = 
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