Physics

2. What is the average speed of an athlete who runs 1500 m in 4 minutes?
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A transparent. dielectric coating is applied to glass (r = 4.r=1, = 0) to eliminate the reflection of red light (wavelength in air of 750 nm). a. What is the required dielectric constant and minimum thickness of the coating? b. If violet light (wavelength in air of 420 nm) is shone onto this glass coating (6-0). what percentage of the incident power will be reflected?
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Determine the magnitude as well as direction of the electric field at point A, shown in the above figure. Given the value of k = 8.99 1012N/C. where, d= 11 cm Q= 12.5 C
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a stone attached to 1m long string is moving with the speed of 5ms in a circle find the centripetal acceleration of the stone
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If a negatively charged particle is placed inside a uniform electric field the electric force that will act on that particle points in what direction in reference to the electric field lines?
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A horse is running on a circular path with constant speed but its direction is changing at every point. It is
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A bicycle tire with a volume of 0.00210 m^3 is filled to its recommended absolute pressure of 495 kPa on a cold winter day when the tire's temperature is -14C. The cyclist then brings his bicycle into a hot laundry room at 32C.a. If the tire warms up while its volume remains constant, will the pressure increase be greater than, less than, or equal to the manufacturer's stated 10% overpressure limit?b. Find the absolute pressure in the tire when it warms to 32 degrees Celcius at constant volume.
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If the final velocity is 0. third equation of motion will be
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An ideal spring is hung vertically from the ceiling. When a 2.0-kg mass hangs at rest from it the spring is extended 6.0 cm from its relaxed length. A downward external force is now applied to the mass to extend the spring an additional 10 cm. While the spring is being extended by the force, the work done by the spring is: a. -3.6 J b. -3.3 F c. -3.4 times 10^-5 J d. 3.3 J e. 3.6 J
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A monatomic gas is measured to have an average speed of 1477 m/s. If thetotal amount of the gas is 2 mol (which equates to a mass of 0.008 kg), whatis the approximate temperature of the gas? (Recall that the equation forkinetic energy due to translation in a gas is KEtranslational = 1 mv2 = 3 nRT,2and R = 8.31 J/(mol-K).)2
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Simple Pendulum: A 34-kg child on an 18-kg swing set swings back and forth through small angles. If the length of the very light supporting cables for the swing is 4.9 m, how long does it take for each complete back-and-forth swing
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"Measurement is essential in our life. Justify the statement.
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Ignore friction. A 20. Lb. Object was lifted to a height of 10 feet by a force of 30. Lb. (a) How much work (ft.Lb) is done by the force? (b) Find the change in potential energy (ft.Lb) of the object
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How can a simulation study be used to learn about a planet we have never visited?In a simulation study you imitate some conditions and characteristics of the real planet. The simulation can be used as a substitute for real data collected on the planet.Simulation studies can be used for planets we have already visited.In a simulation study you imitate as many conditions and characteristics as possible of the real thing, in this case the planet you have not visited. By simulating as many conditions as possible you can visualize what the planet might be like and learn things about it without actually visiting it.Simulation studies cannot be used to learn about a planet we have never visited because we do not know anything about the planet.
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Ella wants to replace old bulbs of her home with new LED bulbs. She buys LED bulb that has inbuilt AC to DC converter of output 5 v and 2.5 A. If the LED is 75% efficient, what would be power dissipated? Also find work done by LED when it is connected to power supply and left for 1 hr 15 minutes?
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An electric fan is running on HIGH. After fan has been running for 1.3 minutes, the LOW button is pushed. The fan slows down to 109 rad/sec in 1.87 seconds. The blades of the fan have a diameter of 6.7 meters and their deceleration rate is 4.7 rad/sec2.What was the initial angular speed of the fan in rev/sec?i =
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What is the de Broglie wavelength of a red blood cell with a mass of 1.00 * 10-11 g that is moving with a speed of 0.400 cm/s? Do we need to be concerned with the wave nature of the blood cells when we describe the flow of blood in the body?
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A scientist who studies the tiny microorganisms of the environment . geologist meteorologist microbiologist entomologist
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A block with a mass of 0.26 kg is attached to a horizontal spring. The block is pulled back from its equilibrium position until the spring exerts a force of 1.2 N on the block. When the block is released, it oscillates with a frequency of 1.4 Hz. How far was the block pulled back before being released?
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A 40 kg boy is standing on the edge of a stationary 30-kg platform that is free to rotate without friction. The boy tries to walk around the platform in a counterclockwise direction. As he does: a. the platform doesn't rotate. b. the platform rotates in a clockwise direction just fast enough so that the boy remains stationary relative to the ground. c. the platform rotates in a clockwise direction while the boy goes around in a counterclockwise direction relative to the ground. d. both go around with equal angular velocities but in opposite directions
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The temperature of a body falls from 30C to 20C in 5 minutes. The airtemperature is 13C. Find the temperature after a further 5 minutes.
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A projectile is launched straight upwards at 75 m/s. Three seconds later, its velocity is...?
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A and B are 0.200m apart in an electric field. If 800J of work are reuqired to move a 2.00 Columb charge from A to B, what is the electric field stregth?
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Which of the following is an ethical question? A. How do we clone humans? B. Can we clone humans? C. Will cloning technology be useful? D. Do clones have the same rights as humans?
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