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For the solid beam ABC shown in the figure, the brass rod has a cross-section of 30 x 30 mm with Eb = 85 GPa and the copper rod 20 x 20 mm and Ec = 120 GPa . A) Compute the stresses in the bars. B) Assume the stress in brass = 35 MPa, at what maximum di
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Cheetahs have a top speed of 120km/h and can accelerate at a constant rate at 9.5m/s^2. How long would it take a cheetah, stalking it’s prey at 4.2m/s, to reach it’s top speed?
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A thin wall copper tube of radius 5 mm is used to transport refrigerant. Heat is lost to the ambient, which is at a lower temperature. Verify that there is an optimum thickness associated with the app
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A clever engineer designs a “sprong” that obeys the force law Fx = -q(x – xe )^3, where xe is the equilibrium position of the end of the sprong and q is the sprong constant. For simplicity well let xe = 0 Then Fx = -qx^3. a) What are the units of q? b) D
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Convert 600 mm Hg to atm. a. 0.789 atm \ b. 4.24 \times 10^5 atm \ c. 38.0 atm \ d. 18.6 atm \
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When an apple falls from a tree, and strikes the ground without bouncing, what happens to its momentum?
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A 6.8 times10-2-kg tennis ball, traveling at 21 m/s , hits a wall, rebounds with the same speed in the opposite direction, and is hit again by another player, causing the ball to return to the wall a
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An electric turntable 0.780 m in diameter is rotating about a fixed axis with an initial angular velocity of 0.280 rev/s and a constant angular acceleration of 0.882 rev/s^2. What is the magnitude of the resultant acceleration of a point on the rim at t
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A sphere of solid aluminum has a diameter of 2.540 cm at 30.00degrees C. The average coefficient of linear expansion for aluminum is 2.200 \times 10^{-5} (degrees C^{-1}). (a) Find the diameter of the sphere (in cm) when its temperature is raised to 80.00
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You hold your physics textbook in your hand. (Assume that no other objects are in contact with the book.) 1) Identify the forces acting on the book. a) book on hand. b) hand on book. c) floor on book
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In the following circuit diagram, R_1 = 5R and R_2 = 15R, where R = 45 space Omega. There is P = 4.5 space W dissipated across resistor 2. a. What is the voltage across the battery? b. How much pow
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An insulation layer is added to a pipe to reduce heat loss from the pipe. as shown in the figure. The outer radius of the pipe is r_1, and the outer radius of the insulation layer is r_2. The thermal conductivity of the insulation material is k. The surfa
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The evaporator of a refrigeration cycle is basically a heat exchanger in which a refrigerant is evaporated by absorbing heat from a fluid. Refrigerant-22 enters an evaporator at 200 kPa with a quality
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If 125 J of heat energy is applied to a block of silver weighing 29.3 g, by how many degrees will the temperature of the silver increase?
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Which one of the following objects (all initially at the same temperature) will be most efficient in losing heat? a) a dull black box in vacuum b) a polished silver box in vacuum c) a box with an e
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Use the coefficient of volume expansion to estimate the density of water as it is heated from 60 F to 130 F at 1 atm. Compare your result with the actual density.
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A helium-neon laser beam has a wavelength in air of 633 nm. It takes 1.33 ns for the light to travel through 32.0 cm of an unknown liquid. Part A: What is the wavelength of the laser beam in the liquid?
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Two brothers leave from the same point driving in opposite directions, the first brother driving at 65 miles per hour and the second at 60 mph. The first brother has a one-hour head start.
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The figure shows a test charge q between the two positive charges. Find the force (in newtons) on the test charge for q = -3 ?C. Give a positive answer if the force is to the right and a negative answ
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The amplitude of a system moving with simple harmonic motion is doubled. The total energy will then be ________.
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Two very large, nonconducting plastic sheets, each 10.0 cm thick, carry uniform charge densities sigma_1, sigma_2, sigma_3 and sigma_4 on their surfaces, as shown in the following figure. There surfac
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Radio waves travel at the speed of light, which is 3.00 times 10^8 m/s. What is the wavelength for a FM station broadcasting at 105.9 MHz ?
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Which is the correct statement regarding the directions of the moments produced by F about points B, C and D, respectively?
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A simple generator has a 480-loop square coil 22.0 cm on a side. How fast must it turn in a 0.550-T field to produce a 120-V peak output?
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Coherent light of wavelength 633 nm from a He-Ne laser falls on a double slit with a slit separation of 0.103 mm. An interference pattern is produced on a screen 2.56 m from the slits. Calculate the separation on the screen of the two fourth-order bright
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A water pump that consume 2 kW of electric power when operating is claimed to take in water from a lake and pump it to a pool whose free surface is 30 m above the free surface of the lake at a rate of
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Three people are standing on a horizontally rotating platform in an amusement park. One person is almost at the edge, the second one is (3/5)R from the center, and the third is (1/2)R from the center. 1) If the period of rotation of the first person is T
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Define stress, normal stress, shear stress and pressure.
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A toy plane with a mass of 1.01 kg is tied to a string and made to travel at a speed of 24 m/s in a horizontal circle with a 16-m radius. The person holding the string pulls the plane in, increasing t
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Steam enters the tubes of a shell-and-tube heat exchanger at 20 bars and 400 ? C, and leaves at 200 ? C. The steam is cooled by passing air initially at 1.5 bars and 27 ? C on the outside of the tubes
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A truck driver travels at 59 miles per hour. The truck tires have a diameter of 30 inches. What is the angular velocity of the wheels in revolutions per minute (rpm)?
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State the functions of double wall, silver wall and cork stopper in a vacuum flask?
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A continuous stream of water is flowing out of a faucet and falling into a sink below. Explain why this stream of water is narrower at the bottom (near the sink) than at the top (near the faucet).
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The loudness of a sound is measured in decibels. The decibel level of a sound is given by the formula D = 10 log (I/I_(o)), where D is the decibel level (dB), I is its intensity in watts per square me
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An object is placed in front of a biconcave lens whose focal length is -30 cm. Use a ray diagram to show where the image is located, and what are its characteristics if the object distance is 20 cm?
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4000J of heat is applied to a 1.5kg silver pendant initially at a temperature of 150 ? C . Determine its final temperature. (Latent heat=336jkg-1, specific heat capacity=233 j/kg.k)
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You have a 170-ohm resistor and a 0.370 H inductor. Suppose you take the resistor and inductor and make a series circuit with a voltage source that has a voltage amplitude of 33.0 V and an angular fre
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Find the magnitude and direction in the 2.0 ohm resistor in the circuit (Let R = 2.5 ohm and V = 1.5 V.)
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Mason lifts a box off the ground and places it in a car that is 0.50 meters high. If he applies a force of 8.0 newtons to lift this suitcase, what is the work done? A. 0 joules B. 4.0 joules C. 4.
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A baby elephant weighs 200 pounds at birth. Seven years later, the elephant’s weight is 3,000 pounds. What is the rate of change of the weight of the elephant?
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