Master Physics with Fun Quizzes & Brain Teasers!

mizar and alcor (also called the horse and rider) have been known since ancient times. which of the following statements is not true about them. group of answer choices they were once used as a vision test. they are a multiple star system with a total of six stars orbiting each other. they are held together with a force of gravity. one of the stars will be exploding (supernova) soon. they are found in the big dipper.
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Two long, straight wires are separated by a distance of 12.2 cm and carry parallel currents. One wire carries a current of 2.51 A ; the other carries a current of 4.33 A. What is the magnitude of the total magnetic field midway between the two wires?
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Two cars collide at an intersection, crumple, and stick together. They skidded to a stop, hitting a telephone pole 30 ft North, 40 ft East of the intersection. From the skid marks it was estimated that the cars were moving at 20 mph just after the collision. Suppose the cars each have a mass of about 1000kg: If car 1 was approaching the intersection from the West and ear 2 from the South, what were their respective speeds just before the collision? Answer (to check your work): Vear 1 = 32 mph: Vear 2 = 21 mph.
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if a dog ages 7 years for 1 human year, what would be the relative velocity, if these relative clocks were phrased kinematically (ie. using the lorentz time dilation transformation formula)?
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what will be the energy change associated with converting 75.0 grams of ice at -25.00 c to liquid water at 37.00 c?
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what is the partial pressure of oxygen when this mixture is delivered at a total pressure of 7.5 atm a t m ?
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A metal rod .76 m long moves with a speed of 2 m/s perpendicular to a magnetic field. If the induced emf between the ends of the rod is .45 V what is the strength of the magnetic field?
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what is the minimum sample rate that should be used for a signal that ranges from 300hz to 3khz
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A child on a freely rotating merry-go-round moves from near the center to the edge. Will the rotational velocity of the merry-go-round increase, decrease, or not change at all? Explain.a The rotational velocity must increase to conserve angular momentum because the rotational inertia of the merry-go-round will be less with the child near the edge.b. The rotational velocity will not change because there is no change in the mass or the angular momentum of the merry-go-round.c. The rotational velocity must decrease to conserve angular momentum because the rotational inertia of the merry-go-round will be greater with the child near the edge.
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what is the order of magnitude wavelength for visible light?A. 0.5 angstromsB. 0.5 nanometersC. 0.5 micrometersD. 0.5 millimetersE. 0.5 metersF. 0.5 kilometers
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what is the total energy (in mev ) released in the beta-minus decay of 3h?
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A 5 kg mass is attached to a spring that is hanging vertically. The spring is stretched 0.25 m from its equilibrium position. What is the spring constant? What mass would be required to stretch the spring three times the distance?
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what heat transfer mechanisms (conduction, convection, or radiation) are involved when heat flows through a glass windowpane? explain.
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Two particles, each of mass m, are moving with velocity -v and 2v. The kinetic energy at the center of mass is? A. (1/2) mv^2 B. mv^2 C. (1/4)mv^2 D. 4mv^2
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In an experiment, a changing magnetic field is used to create and an electric field in a circular conductor. The students generate a magnetic field of 2 T directed into the page in a circular region of radius 0.20 m. A circular ring of radius 0.10 m is placed concentric with the magnetic field, as shown. The magnetic field is decreased to zero in 0.50 seconds. Which of the following indicates the magnitude of the electric field in the conductor and indicates the Maxwell equation associated with determining the electric field? A. According to Gauss's law, the electric field will be 0.20 N/C B. According to Ampere's law, the electric field will be 0.20 N/C C. According to the Maxwell-Faraday equation, the electric field will be 0.20 N/C D. According to Ampere's law, the electric field will be 0.80 N/C E. According to the Maxwell-Faraday equation, the electric field will be 0.80 N/C
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A 1.2-cm-tall object is 22 cm in front of a convex mirror that has a -57 cm focal length.1) Calculate the position and height of the image. (s')2) Express your answer to two significant figures and include the appropriate units. (h')3) State whether the image is in front of or behind the mirror, and whether the image is upright or inverted.
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if the nucleus found in part a has an atomic mass of 65.9289 u, what is the maximum kinetic energy of the emitted electron?
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at point p the magnetic field due to a long straight wire carrying a current of 2.0 a is 1.2 t. how far is p from the wire? ( 0 = 4 10 -7 t m/a)\
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A block of mass m= 6.00 kg is attached to the end of an ideal spring. Due to the weight of the block, the block remains at rest when the spring is stretched a distance h= 5.00 cm from its equilibrium length. (Figure 1)The spring has an unknown spring constant k. Take the acceleration due to gravity to be g = 9.81 m/s2 .Suppose that the block gets bumped and undergoes a small vertical displacement. Find the resulting frequency f of the block's oscillations about its equilibrium position.Express your answer in hertz.
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for the amplifier in fig. 10.37(a), if r(;] = 3 mq, rg2 = 2 m2, and /?sig = 500k2, find the value of the coupling capacitor ccl (specified to one significa
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what is the maximum possible angular momentum lll (as a multiple of ) of a hydrogen atom with energy -0.850 evev ?
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if the shm is described as x(t) = 0.5cos(20t ), the magnitude of the maximum acceleration is
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when 0.107 g of zn(s) is combined with enough hcl to make 53.2 ml of solution in a coffee-cup calorimeter, all of the zinc reacts, raising the temperature of the solution from 22.2 c to 24.5 c.
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What are interference and diffraction? Under what circumstances do they occur?
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