Master Physics with Fun Quizzes & Brain Teasers!

what force is this?
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A train moves away from a station at 50 m/s. The train blows its whistle that has a frequency of 520 Hz. What is the frequency heard at the station? Take the speed of sound to be 340 m/s.440 Hz450 Hz600 Hz610 Hz
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a circular loop of wire is placed in a magnetic field so that the field points in a direction perpendicular to the plane of the loop. if the magnitude of the field is 0.621 t, and the radius of the loop is 4.37 cm, find the magnetic flux through the loop.
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if your power output is 128 w , and the mass of the bucket and the water in it is 6.00 kg , with what speed can you raise the bucket? ignore the weight of the rope.
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42 cal of heat are required to increase the temperature of a 30 g piece of an unknown substance from 20 to 27 c and the specific heat capacity of the substance is _____ cal/g degc.
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If two gases have the same volume and thereare two moles of each gas, gas A is at 1600 K,gas B is at 800 K and gas A has the pressureof 6 atm, find the pressure of gas B.
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a charge q1=6.5c is at the origin, and a charge q2=2.42c is on the x-axis at x = 1.00m. find the magnitude of net force acting on a charge q3= 1.4c located at x=0.55 m.
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is the thermal efficiency of an ideal cycle greater than that of a carnot cycle operating between the same temperature limits?
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true/false. straighterline meissner's corpuscles sense deep pressure.
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W A 10.0 kg mass is at the origin. A 20.0 kg mass is 0.500 m to the left of it, and a 30.0 kg mass is 1.25 m to the right of it: What is the net gravitational force on the 10.0 kg mass? [?] x 10l ?] N Coefficient (green) Exponent (yellow) HAnal Frannd AA,kc Book'' '03 888
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A metal sphere with an excess of 11 electrons touches an identical metal sphere with an excess of 15 electrons. After the spheres touch, find the number of excess electrons on the second sphere.
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A 1.05 kg block is attached to a spring with spring constant 16.0 N/m. While the block is sitting at rest, a student hits it with a hammer and almost instantaneously gives it a speed of 41.0 cm/s. What are The amplitude of the subsequent oscillations? Express your answer with the appropriate units. The block's speed at the point where x= 0.450 A? Express your answer with the appropriate units.
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An axle passes through a pulley. Each end of the axle has a string that is tied to a support. A third string is looped many times around the edge of the pulley and the free end attached to a block of mass m which is held at rest When the block is released, the block falls downward. Consider clockwise to be the positive direction of rotation, frictional effects from the axde are negligible, and the string wrapped around the disk never fully unwinds. The rotational inertia of the pulley is 1/2 MR^2 about its center of mass. Which of the following graphs, if any, shows the angular velocity of the pulley as a function of time t after the block is released from rest?
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"A crew member of a spaceship measures the length of the ship to be 200 mm. However, an observer on a nearby space station measures the ship's length to be 120 mm. What is the speed of the spaceship relative to the space station?Express your answer with the appropriate units."
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Which one of the following phrases best describes the term work function?A) The minimum energy required to vaporize a metal surfaceB) The work required to place a charged particle on a metal surfaceC) The minimum energy required to remove electrons from a metal surfaceD) The minimum energy required to remove an atom from a metal surfaceE) The work done by electromagnetic radiation when it hits a metal surface
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A 5-in wide polyamide A-2 belt connects the driver pulley (d = 3 in, 1500rpm, providing 2.5 hp) tothe driven pulley 9 ft away. If the transmission ratio is 1/3, determine:a) centrifugal force, initial tension, and forces on the loose and tight sidesb) allowable power and safety factor if Ks is 1.25.c) is the friction between the belt and pulleys large enough?
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"The wave speed in an aluminum wire with a radius of 1.00 mm is 120 m/s. What is the tension in the wire? The density of aluminum is 2.70 x10^3 kg/m^3.What formula do we use and how do we solve?"
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a silver wire has a resistance of 13.2 ohms at 20 c. what resistance does it have at 39 c
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a train moves away from a station at 50 m/s. the station whistle blows with a frequency of 520 hz. what is the frequency heard on the train? take the speed of sound to be 340 m/s.
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when an electron trapped in a one-dimensional box transitions from its n = 2 state to its n = 1 state, a photon with a wavelength of 678.9 nm is emitted. what is the length of the box (in nm)?
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an air bubble originating from an underwater diver has a radius of 8 mm at some depth h. when the bubble reaches the surface of the water, it has a radius of 10.5 mm. assuming the temperature of the air in the bubble remains constant, determine the depth of the diver. the acceleration due to gravity is 9.8 m/s 2 .
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When one of the authors was a teenager, the rate of rotation for popular music records on a record player was 78 RPM. The rotational velocity in rev/s is____?The number of revolutions made in 5 s is_____
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A step-down transformer produces a voltage of 7.0V across the secondary coil when the voltage across the primary coil is 120V .What voltage appears across the primary coil of this transformer if 120V is applied to the secondary coil?
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Please choose the correct answer for the upper-level divergence regions. a) Upper level divergence region is behind trough b) upper level divergence region is ahead of trough
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