It seems the universe is full of angular momentum. Planets revolve and orbit stars, stars revolve and orbit galactic centres even sub atomic particles spin.
Yet the origin of the universe was the big bang where everything exploded outward froma point source. As I understand it there is a law of conservation of angular momentum saying it cannot be created or destroyed onlt transferred. So I am puzzled where did all the angular momentum come from?
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1). Explain the following issues with a short essay (with total number of words less than 300)
(a) Gauss law in electrostatics.
(b) Ampere’s law in magnetostatics.
(c) Faraday’s induction law.
(d) Displacement current.
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Consider a two-dimensional universe where Maxwell's equations are valid (their corresponding two-dimensional). Derive a wave equation.
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When an object is located very far away from a convex mirror,
the image of the object is 12.0 cm behind the mirror. Using a ray
diagram drawn to scale, determine where the image is located when
the object is placed 6.0 cm in front of the mirror. Note that the
mirror must be drawn to scale also. In your drawing, assume that
the height of the object is 3.0 cm.
cm ---Select--- in front of behind the mirror
As an aid in working this problem, consult Concept Simulation
25.2.
A 5.0-cm-high object is situated 16.0 cm in front of a concave
mirror that has a radius of curvature of 8.0 cm. Use a ray diagram
drawn to scale, measure the following. The mirror must be drawn to
scale.
(a) the image distance (include the sign)
cm ---Select--- in front of the mirror in back of the
mirror
(b) the height of the image
cm ---Select--- upright inverted
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An extremely thin sheet of glass is being inspected at the factory. Illuminated by white light at near-normal incidence, the film-like sheet is 0.402 µm thick and has air on both sides. If the glass has a refractive index of 1.52, what wavelength of visible light (in nm) does it reflect most strongly? (The wavelengths of visible light range from 400 to 700 nm.)
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A radio antenna broadcasts a 1.0 MHz radio wave with 29.0 kW of power. Assume that the radiation is emitted uniformly in all directions.
What is the wave's intensity 25.0 km from the antenna?
The answer is 3.69×10−6 W/m^2
What is the electric field amplitude at this distance?
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A 336-kg crate rests on a surface that is inclined above the horizontal at an angle of 17.2°. A horizontal force (magnitude = 405 N and parallel to the ground, not the incline) is required to start the crate moving down the incline. What is the coefficient of static friction between the crate and the incline?
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A catapult launches a test rocket vertically upward from a well, giving the rocket an initial speed of 80.8 m/s at ground level. The engines then fire, and the rocket accelerates upward at 4.20 m/s2 until it reaches an altitude of 990 m. At that point its engines fail, and the rocket goes into free fall, with an acceleration of ❝9.80 m/s2. (You will need to consider the motion while the engine is operating and the free-fall motion separately.)
(a) For what time interval is the rocket in motion above the ground? s
(b) What is its maximum altitude? km (
c) What is its velocity just before it hits the ground? m/s
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When do the centers of gravity and mass coincide? When they don’t? Explain why is the center of gravity of the Flame Towers (building in Baku, lookup in google) is a bit below their center of mass?
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1-Why doesn't the force of gravity change the speed of a satellite in circular orbit?
2-A circularly moving object requires a centripetal force. What supplies this force for satellites that orbit the Earth?
3-A 'geosynchronous' Earth satellite can remain nearly directly overhead in Singapore, but not in San Francisco. Why?
4-True or false: For orbits of greater altitude, the period is longer.
5- Fill in the blank:
____(a)______gathered the data that were used to show that the planets travel in elliptical orbits around the sun___(b)_______discovered the orbits were elliptical.______(c)_______explained them.
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Question 4(3pts)
State the definitions of elastic, inelastic, and completely inelastic collisions. Give an example of a situation where the final kinetic energy is greater than the initial value.
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An airplane is flying with a velocity of 240 m/s at an angle of 30.0° with the horizontal, as the drawing shows. When the altitude of the plane is 2.4 km, a flare is released from the plane. The flare hits the target on the ground. What is the angle θ?
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PLEASE PLUG IN YOUR OWN VALUES FOR THE GIVEN PROBLEM AND SOLVE:
A projectile is fired with an upward aim from a cliff and lands somewhere away and below the cliff. You are asked to find the vertical distance between where the projectile lands and the highest point in the trajectory of the projectile.
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Obtain the equation of motion for a 1.25-g mass, at the end of a perfectly elastic spring which, when stretched 3.75 cm from equilibrium and then released from rest, undergoes simple harmonic motion with a period of 0.016667 s. B.) Find the (i) spring constant (ii) maximum velocity and (iii) total energy of the mass. C.) For the above spring find the positions for which the potential energy is one-third the kinetic energy.
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