Master Physics with Fun Quizzes & Brain Teasers!

In an experiment with cosmic rays, a vertical beam of particles that have charge of magnitude 3e and mass 12 times the proton mass enters a uniform horizontal magnetic field of 0.345 T and is bent in a semicircle of diameter d = 80.0 cm, as shown in the figure below.(a) Find the speed of the particles and the sign of their charge.(b) Is it reasonable to ignore the gravity force on the particles?(c) How does the speed of the particles as they enter the field compare to their speed as they exit the field? (They exit with greater speed/ They exit with less speed/ They exit with the same speed.)
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Find the direction of the force that our planet's magnetic field exerts on this cord if is oriented so that the current in it is running vertically upward.Answer choices:a.) The force is directed from east to west.b.) The force is directed from west to east.c.) The force is directed from north to south.d.) The force is directed from south to north.
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what is the length of a one-dimensional box in which an electron in the n=1n=1 state has the same energy as a photon with a wavelength of 500 nmnm ? express your answer in nanometers.
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the density of air is 1.3 kg/m3 and the speed of sound in air is 340 m/s. the displacement amplitude of a tone with angular frequency 1300 rad/s is 2.0108 m. what is the pressure amplitude?
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A longitudinal wave of amplitude 3.0 cm, frequency 1.8Hz , and speed 4.0m/s travels on an infinitely long Slinky.How far apart (the closest distance) are the two nearpoints on the Slinky that at one particular time both have the maximum displacements from their equilibrium positions?Express your answer to two significant figures and include the appropriate units.x =
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If a particle of mass m= 0.3 kg and q= 1.4 c was released from rest at point c what would be the particle's velocity when it reached point d? (answer should be in units m/s)
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estimate the total mass of the earth's atmosphere? (the radius of the earth is 6.37 106 m, and atmospheric pressure at the surface is 1.01 105 n/m2.)
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a child with mass 38.7 kg is running in circular motion around a pole at a distance 2.39 m from the pole. when the child has a speed of 7.83 m/s, what is the child's angular momentum about the pole?
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A bell produces sound energy at a rate of 4.00*10^-3W and radiates it uniformly in all directions. What is the intensity of the wave 100.0m from the bell?
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a balloon filled with helium plus air at atmospheric pressure is designed to support a mass of 102 kg (payload empty balloon). air density is 1.29 kg/m3 , helium plus air density in the balloon is 0.372 kg/m3 , and helium density is 0.179 kg/m3 . ignoring the volume of the payload, find the volume of the balloon. answer in units of m3 .
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Find the excitation energy from the ground level to the third excited level for an electron confined to a box that has a width of 0.360 nm . The electron makes a transition from the n=1 to n= 4 level by absorbing a photon. Calculate the wavelength of this photon.
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what is the mass of a solid sphere with radius 5.0 cm , that has 2.5 j of kinetic energy when it rotates at 34 rad / s ?
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be sure to answer all parts. how much heat is required to evaporate 104.2 g of water at 100.0c? the molar heat of vaporization for water is 4.07 104 j/mol.
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what is the magnitude and direction of the electric force on a 3.0 c charge at a point where the electric field is 2800 n/c and is directed along the y axis.
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at what points in the plane of the page (besides points at infinity), is the magnetic field due to the currents zero?
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what is the distance between lines on a diffraction grating that produces a second-order maximum for 683-nm red light at an angle of 61.0?
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How does the slit width affect the line separation?
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when calculating a batterys capacity using: what is the main underlying assumption regarding the battery?
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A 0.30kg0.30kg ball is attached at the end of a 0.90m0.90m long stick.The ball and stick rotate in a horizontal circle. Because of air resistance and to keep the ball moving at constant speed,a continual push must be exerted on the stick, causing a 0.036Nm0.036Nm torque. Determine the magnitude of the resistive force that the air exerts on the ball opposing its motion. What assumptions did you make?
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for what soap film thickness, other than the minimum thickness, will constructive interference occur?
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identify the sub-level from which the electron is removed when the first ionisation energy of germanium is measured
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from the list of statements associated with kinetics, shown below, select the ones that are true: (a) temperature generally increases the rate of a reaction. (b) the activation energy of a reaction does not depend on the energy difference of reactants and products. (c) temperature generally reduces the activation energy. (d) the rate law of a reaction is an expression that describes the influence of concentration on the rate constant. (e) the rate of a reaction depends on the change in concentration over time.
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A straight wire produces a magnetic field of 6.1 10?6T at a distance of 25 cm .What is the current in the wire? I =
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Charge is uniformly distributed with charge density rho inside a very long cylinder of radius R.Find the potential difference between the surface and the axis of the cylinder.Express your answer in terms of the variables rho, R, and appropriate constants.VsurfaceVaxis =
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