A mass resting on a horizontal, frictionless surface is attached to one end of a spring; the other end is fixed to a wall. It takes 3.7 J of work to compress the spring by 0.14 m . If the spring is compressed, and the mass is released from rest, it experiences a maximum acceleration of 12 m/s2.
Find the value of the spring constant.
Find the value of the mass.
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3. A positive point charge q = +3 µC is placed on the y axis at y = +5 cm. A negative point charge -q = -3 µC is placed at the origin.
a) At how many points on the y axis could an additional positive charge +q be placed without changing the potential energy of the system?
b) Calculate the work done by the field to bring in an additional point charge +q from infinity to the point A. (The other two charges are held in position during this procedure.
c) What is the potential energy U of the square arrangement of charges at right?
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An iron boiler of mass 180 kg contains 730 kg of water at 11 ∘C. A heater supplies energy at the rate of 58,000 kJ/h. The specific heat of iron is 450 J/kg⋅C∘, the specific heat of water is 4186 J/kg⋅C∘, the heat of vaporization of water is 2260 kJ/kg⋅C∘. Assume that before the water reaches the boiling point, all the heat energy goes into raising the temperature of the iron or the steam, and none goes to the vaporization of water. After the water starts to boil, all the heat energy goes into boiling the water, and none goes to raising the temperature of the iron or the steam.
How long does it take for the water to reach the boiling point from 11 ∘C∘C?
How long does it take for the water to all have changed to steam from 11 ∘C∘C?
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Answer briefly the following.
a) What is a primitive cell and write the basic simple cell
names.
b) Write the symmetry operations in crystals.
c) Write the diffraction condition in the Brilloun region with the
opposite lattice vector.
d) Describe Bragg's law and determine the condition of X-rays to be
diffraction in crystals.
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The potential of a particle is given as V (x) = -Vδ (x), with V being a positive number. Find the wave function and energy of the bounded states of this particle.
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A solenoidal coil with 20 turns of wire is wound tightly around another coil with 320 turns. The inner solenoid is 21.0 cm long and has a diameter of 2.50 cm . At a certain time, the current in the inner solenoid is 0.140 A and is increasing at a rate of 1800 A/s .
For this time, calculate the mutual inductance of the two solenoids;
For this time, calculate the emf induced in the outer solenoid by the changing current in the inner solenoid.
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A continuously operating coherent Binary Phase Shift Keying (BPSK) system is made by an engineer. He claims that it is having an average error probability of 10-5. The system produced 1000 errors in a day when tested with a data rate of 500 bits/s and the single-sided noise power spectral density is No=10-10 W/Hz. He also claim that the system is capable of maintaining the error rate even if the received power is as low as 10-6 W. Do you agree with his claims? Give justifications to your answer.
please, I need a clear answer.
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Which assumption is true of an ideal gas?
a. The gas has volume because the particles take up space.
b. The particles experience no inter-molecular attractive
forces.
c. The particles undergo inelastic collisions with the surface of
their container.
d. The ideal gas model is not accurate under most conditions.
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A swimmer is peacefully floating motionless in a lake. Determine the fraction of the
total volume of her body which remains visible above the water, given that the density
of her body is 920 kg/m3, and the density of the lake water is 1025 kg/m3.
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The moon has a mass of about 7.3x1022kg amd a radius of 1738km.
a)Calculate the escape speed from the surface of the moon. Express the answer in km/sec.
b) A spacecraft of mass 250kg is launched from the surface of
the moon at a speed of 1500m/sec. Using conservation of mechanical
energy, compute the maximum distance reached by the spacecraft, at
which the spacecraft comes to a stop.
c) if the spacecraft is launched with an initial speed of 5500m/sec
from the surface of the moon, use conservation of mechanical energy
to determine how fast the spacecraft will be traveling when it is
very far from the moon.
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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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