Master Physics with Fun Quizzes & Brain Teasers!

if the drag on one side of a flat plate parallel to the upstream flow is d when the upstream velocity is u, what will the drag be when the upstream velocity is (a) 8u, (b) u/8? assume laminar flow.
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a tank contains 19 kg of dry air and 0.2 kg of water vapor at 37 0c and 91 kpa total pressure. determine (1) the specific humidity. (2) the relative humidity. 15.129 (3) the volume of the tank. new problem (resets attempts)resets remaining: 9submitattempts remaining: 28
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in the ac circuit shown, the component values are chosen such that , , and . find the amplitude of the sinusoidal inductor current, , if the two source voltages are: 18 volts, 5 volts. express your answer in units of milli-amps (ma).
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what positive angular frequency leads to maximum practical resonance?
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a car approaches a train station with a speed of 30 m/s . a stationary train at the station sounds its 167- hz horn.what frequency is heard by the driver of the car?
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a 1150-kg car is held in place by a light cable on a very smooth (frictionless) ramp. what is the tension the cable?
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if you are using edge trigger f and edge trigger g, can you set their priority to the same level? what happens if the two triggers occur at the same time
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Suppose you leave a 110W television and two 100 W lightbulbs on in your house to scare off burglars while you go out dancing. if the cost of electric energy in your town is $0.12/kWh and you stay out for 4.0 h, how much does this robbery prevention measure cost?
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A 15 kg runaway grocery cart runs into a spring with spring constant 270 N/m and compresses it by 64 cm.What was the speed of the cart just before it hit the spring?
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m = 14.24706 grams, = 0.003 grams. (uncertainty) in = 7.35 kg = 4*10-1kg (uncertainty) (show all work)
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A 128 g ball is tied to a string. It is pulled to an angle of 3.60 degrees and released to swing as a pendulum. A student with a stopwatch finds that 17 oscillations take 15.5 s .Part AHow long is the string?
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a 220 mwmw laser pulse is focused with a lens to a diameter of 1.7 mm . part a part complete what is the laser beam's electric field amplitude at the focal point?
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what signal-to-noise ratio is needed to put a t1 carrier on a 50 khz line
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if 49.8 g s is allowed to react as completely as possible with 103.9 g f2(g) , what mass of the excess reactant is left?
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what is the minimum non-zero thickness of the coating that will produce destructive interference for the yellow-green light? _______ nm
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what is the speed of a particle whose momentum is 2.20 mc ?
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If the radius r of a cone is decreasing at a rate of 2 centimeters per minute while its height h is increasing at a rate of 4 centimeters per minute, which of the following must be true about the volume V of the cone?(V=13r2h)(A) V is always decreasing. (B) V is always increasing.
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Use conservation of energy to find the angular velocity of the wheel when the wheel is fully unwound. (Remember that the rotational energy is Erot = I2.)Compute the downward acceleration of a falling wheel of the same shape and size as the one in the laboratory, but made of a different material which is three times as heavy.Suppose the radius of the axle of Maxwells wheel is reduced to the measured value, whereas the disk remains the same.Is the downward acceleration a going to be bigger or smaller? Explain.Find a value for a that is accurate to within a few percent.A disk and a hoop have the same radius and mass. What is the ratio of their moments of inertia?If the Maxwells wheel from this experiment were to rotate twice as fast, how much would its kinetic energy increase?
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when being charged electrical pressure voltage higher than that of the batteryties total cell_____
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What dimensions will produce a box with the largest volume?A manufacturer wants to design an open top box with a square base having a surface area of 108 square inches.
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A refrigerator uses the natural refrigerant carbon dioxide where the compressor brings 0.02 kg/s from 1 MPa, -20C to 6 MPa using 2 kW of power. Find the compressor exit temperature.
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A 90-kg fullback is traveling 5.0 m/s and is stopped by a tackler in 1 s. Calculate (a) the original momentum of the fullback, (b) the impulse imparted to the tackler, and (c) the average force exerted on the tackler.
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A radioactive substance decays exponentially. A scientist begins with 160 milligrams of a radioactive substance. After 12 hours, 80 mg of the substance remains. How many milligrams will remain after 19 hours? 53.39 mg
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on the avogadro constant tab, place the copper (cu) atom on the nano-balance on the left, which will show the average atomic mass of copper rather than the mass of a single copper atom.1. What is the average mass of a copper atom?2. To gain an idea as to how many atoms are in a gram or so of copper, use the larger balance on the right. Press Add atoms to put a scoop of atoms in the weighing dish, and keep adding until the balance registers between 1 and 2 grams. If you dont seem to be making much progress, adjust the exponent using the slider, which will make the scoop size bigger.How many atoms did you need to add?
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