A wheel has an initial angular velocity of 1 rad/s and undergoes an angular acceleration of 10 rad/s^2. (a) How many radians does it rotate in 4 sec? (b) What is its angular velocity at this time?
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An alpha particle with kinetic energy 12.0 MeV makes a collision with lead nucleus, but it is not "aimed" at the center of the lead nucleus, and has an initial nonzero angular momentum (with respect to the stationary lead nucleus) of magnitude L=p0b, where p0 is the magnitude of the initial momentum of the alpha particle and b=1.30×10−12 m . (Assume that the lead nucleus remains stationary and that it may be treated as a point charge. The atomic number of lead is 82. The alpha particle is a helium nucleus, with atomic number 2.)
Part A
What is the distance of closest approach?
Part B
Repeat for b=1.50×10−13 m .
Part C
Repeat for b=1.30×10−14 m .
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The heat capacity, Cp, of liquid carbon disulfide is a relatively constant 78J(molK). However, the heat capacity of solid carbon disulfide varies greatly with temperature. From 99K to its melting point at 161K, the heat capacity of solid carbon disulfide increases linearly from 44 J/(molK) to 57 J/(molK).
The enthalpy of fusion of carbon disulfide is 4390 J/mol.
The absolute entropy of liquid carbon disulfide at 298K is 151 K/(molK).
Estimate the absolute entropy of carbon disulfide at 99K.
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a projectile is launched from ground level to the top of a cliff which is 95 m away and 155 m high. If the projectile lands on top of the cliff 7.6 s after it is fired, what was its initial velocity? (Be careful what you assume).
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Demonstrate that the ground-state wave function for the one-dimensional harmonic oscillator satisfies the appropriate Schrodinger's equation
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An arrow strikes the target at the end of a 27-meter-long lane. It lands at an angle of 4 degrees below the horizontal. What is the initial velocity at which the arrow was launched? Assume that the initial velocity toward the target is entirely horizontal and the angel of the arrow in the target is the direction of the final velocity.
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3 boxes, having masses m1=5kg, m2=10kg and m3=15 kg are stacked "sideways" (i.e., in x-) on a surface with coefficient of kinetic friction 0.7 muk; an external force of magnitude 15 N pushes on the right-most box, making an angle of 30 degrees relative to the horizontal; a second force of magnitude 20 N pushes in the opposite direction on the left-most box, as a result of which all three accelerate uniformly. Determine the numerical value all of the forces acting on each of the boxes (including all normal forces between the boxes), as well as the amount the boxes have moved after a time of 7 seconds. Keep in mind that the normal force acting specifically on the box subject to the external force is changed by the external force...
please make a diagram
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Please Show work
1) A certain medical machine emits x-rays with a minimum wavelength of 0.025 nm. One day, the machine has an electrical problem and the voltage applied to the x-ray tube decreases to 74% of its normal value. Now what is the minimum x-ray wavelength produced by the machine?
?min = _________ nm
2) What is the maximum x-ray energy this machine (with electrical problems) can produce?
Emax = _________ eV
3) The atomic number of an element is 82. According to the Bohr model, what is the energy of a K? x-ray photon?
E = ___________ eV
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A yo-yo has a rotational inertia of 900 g · cm2 and a mass of 100 g. Its axle radius is 3.2 mm, and its string is 120 cm long. The yo-yo rolls from rest down to the end of the string. (a) What is the magnitude of its linear acceleration? (b) How long does it take to reach the end of the string? As it reaches the end of the string, what are its (c) linear speed, (d) translational kinetic energy, (e) rotational kinetic energy, and (f) angular speed?
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1. Water is in the big beaker in the figure on the left. Scale 1 reads 58 newtons, scale 2 reads 908 newtons, and scale 3 reads 0 newtons. The hanging block has a density of 10
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How would you connect a pair of equal resistors across a battery in order to get the most power dissipation in the resistors?
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From a point 96 ft above the ground, a stone is thrown in such a way that it is at the same point: 3 sec after it was thrown, as it was 2 sec after it was thrown. How long does it take the stone to reach the ground?
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The minimum stopping distance for a car depends on the driver’s reaction time and the car’s acceleration when the brakes are applied. A 1000 kg car traveling on a level road at speed 18 m/s travels 15 m (due to driver’s reaction time) before braking starts and then skids with the wheels locked another 30 m. Answer the following questions concerning this stopping process. (Ignore air resistance and assume g = 10 m/s^2.)
a) What is the driver’s reaction time?
b) How long did it take for the car to come to a complete stop: include both segments – the one when the car was still going at a constant speed, and the other one when the car brakes were applied?
c) Sketch a v(t) (I believe it is a velocity-time) graph for the car motion for the entire braking process of the car: from the moment the driver noticed danger to the moment the car completely stopped. Indicate relevant times and velocities on the graph.
d) Show that the magnitude of the net force acting on the car when the car was skidding was 5400 N.
I'm not sure how I should start this. If someone could explain and answer It would be great. (:
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1. If 55.1 cm of copper wire (diameter = 1.18 mm, resistivity = 1.69 × 10-8Ω·m) is formed into a circular loop and placed perpendicular to a uniform magnetic field that is increasing at the constant rate of 12.6 mT/s, at what rate is thermal energy generated in the loop?
2. A rectangular loop (area = 2.7 m2) turns in a uniform magnetic field, B = 3.2 T. When the angle between the field and the normal to the plane of the loop is π/2 rad and increasing at 2.6 rad/s, what emf is induced in the loop?
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