If the radius of the equipotential surface of point charge is 15.2 m at a potential of 2.30 kV, what is the magnitude of the point charge creating the potential?
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Q.1) Projectile motion:A stone is thrown vertically into the air off the edge of a bridge 150ft above a river. If the initial velocity of the rock is 64ft/sec (upward0 and the accleration is constant -32ft/sec2 (downward), find the following:
a. the velocity v(t) after t seconds.
b. The position s(t) of the stone above the river after t seconds.
c. The velocity at which the stone strikes the water.
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1. The electric field generated by a point charge has strength of 180000n/c at a point 1.50 cm from the point charge what is the charge if the field points towards the charge?
2.An electron was accelerated from rest through a potential difference of 9900V. what is the speed at the end?
3.A 100.0pF capacitor consists of two circular plates of radius 0.40mm. how far apart are the plates?
4. A 4.0m m length of gold wire is connected to a 1.5 V battery, and a current of 4.0mA flows through it. What is the diameter of the wire? (the resistivity of gold is 2.24x10^-8)
5.Two parallel plates that are initially uncharged are separated by 1.2mm. What charge must be transferred from one plate to the other if 11.0kj of energy are to be stored in the plates, if area of each plate is 19.0mm?
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Two small metallic spheres, each of mass m = 0.210 g, are suspended as pendulums by light strings of length L as shown in the figure below. The spheres are given the same electric charge of 6.8 nC, and they come to equilibrium when each string is at an angle of ? = 4.85
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After discovering that two hikers have been stranded on Devil's Thumb Pass, the Colorado Search and
Rescue team sends out a plane with supplies for the hikers. Because the hikers are in an isolated location, the
plane has to drop the supplies as it ies overhead. If the plane is 235 m above the hikers and
has a horizontal speed of 200 km/h, how far away from the hikers should the supplies be dropped if they are
to land at the hikers' location? (Hint: the initial y-component of the supplies' velocity is zero
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(a) Two point charges totaling 7.50 µC exert a repulsive force of 0.150 N on one another when separated by 0.812 m. What is the charge (in µC) on each? smallest charge in µC largest charge in µC
(b) What is the charge (in µC) on each if the force is attractive? smallest charge in µC largest charge in µC
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A car initially traveling at 25.7 m/s undergoes a constant negative acceleration of magnitude 1.80 m/s2 after its brakes are applied.
(a.) How many revolutions does each tire make before the car comes to a stop, assuming the car does not skid and the tires have radii of 0.340 m? (rev)
(b.) What is the angular speed of the wheels when the car has traveled half the total distance? (rad/s)
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A softball is hit over a third baseman's head with speed v0 and at an angle θ from the horizontal. Immediately after the ball is hit, the third baseman turns around and runs straight back at a constant velocity V=7.00m/s, for a time t=2.00s. He then catches the ball at the same height at which it left the bat. The third baseman was initially L=18.0m from the location where the ball was hit at home plate.
1) Find a vector expression for the velocity v⃗ of the softball 0.100 s before the ball is caught.
Use the notation vx, vy, an ordered pair of values separated by a commas Express your answer numerically in meters per second to three significant figures.
2) Find a vector expression for the position r⃗ of the softball 0.100 s before the ball is caught.
Use the notation x, y, an ordered pair of values separated by a comma, where x and yare expressed numerically in meters, as measured from the point where the softball initially left the bat. Express your answer to three significant figures.
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The coefficient of expansion for liquids is:
a) greater than that for solids
b) different for different temperatures
c) smaller as the volume changes
d) greater as the volume changes
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What is the difference between phase velocity and phase angle?
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What theoretical explanations exist for the fact that there are three generations of leptons and quarks?
I'm not so much asking why there are exactly 3 generations, but rather what makes electron, muon and tau differ. Also, since the three families of quarks don't have to be a priori related to the three families of leptons, I'm interested in answers for either quarks, leptons, or both.
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3. A cube of Brass (B = 70 GPa) measuring 1.0 m on each side is submerged under water. It is lowerd to a depth where a force "F" is acting perpendicularly into each side, reduces the cube's volume by 1.8 %.
(a) Calculate the size of this force.
2.A researcher examines a piece of fresh human cartilage, with an area of 1.9 cm2. She observes that when subjected to a tensile force of 194 N it stretches by 4.8 %.
(a) Calculate the elastic modulus of cartilage.
1. A student pushes on the end of a helical spring, which in turn presses a 1.25 kg, wooden block onto a vertical wall. The coefficient of static friction between the block and wall is 0.5. She compresses the spring 5.2 cm.
(a) Calculate the minimum spring constant necessaary to prevent the block from sliding down the wall.
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1. Explain the physical reason that this change in Planck's expression avoided the ‘Ultraviolet Catastrophe’.
2. Calculate the probability of finding the particle within the finite wall of the box when the particle is in the lowest and highest bound energy states of the box with one finite wall described above. Assume that the coefficient D is approximately D= (2/L)^1/2
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Every second at a particular waterfall, some 6996 m3 of water falls a distance of 37 m. What is the increase in entropy in kJ/K, per second due to the falling water? (Assume a 23°C environment).
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