Master Physics with Fun Quizzes & Brain Teasers!

An Australian emu is running due north in a straight line at a speed of 13.0 m/s and slows down to a speed of 10.0 m/s in 3.30 s. (a) What is the magnitude and direction of the birds acceleration? (b) Assuming that the acceleration remains the same, what is the birds velocity after an additional 1.20 s has elapsed?
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Find the average velocity if the takeoff velocity of an airplane on a runway is 300 km/hr with an acceleration of 1 m/s2 . A) 30 sec B) 41.7 sec C) 72.2 sec D) 83.33 sec
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Two large rectangular aluminum plates of area 180 cm2 face each other with a separation of 3 mm between them. The plates are charged with equal amount of opposite charges, 17 C. The charges on the plates face each other. Find the flux (in N m2/C) through a circle of radius 3.3 cm between the plates when the normal to the circle makes an angle of 4 with a line perpendicular to the plates. Note that this angle can also be given as 180 + 4. N m2/C
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g 0 g bullet is fired horizontally into a 1.20 kg wooden block resting on a horizontal surface. The coefficient of kinetic friction between block and surface is 0.20. The bullet remains embedded in the block, which is observed to slide 0.390 m along the surface before stopping. Part A What was the initial speed of the bullet? Express your answer with the appropriate units. v = nothing
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In certain ranges of a piano keyboard, more than one string is tuned to the same note to provide extra loudness. For example, the note at 110 Hz has two strings at this frequency. If one string slips from its normal tension of 596 N to 538.00 N, what beat frequency is heard when the hammer strikes the two strings simultaneously
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Please Help!!!!A helicopter flies with an airspeed of 42.5 m/s [W]. If the wind is traveling with a velocity of 25.0 m/s [E30S] relative to the ground then determine the velocity of the helicopter relative to the ground. a) Use the data from the question to determine the velocity components for the helicopters speed relative to the air and the winds speed relative to the ground. b) Use your velocity components from part (a) and determine the resultant velocity for each component. (In other words, determine the resultant horizontal component for the helicopters ground speed and the resultant vertical component for the helicopters ground speed). c) Using your data, determine the resultant velocity of the helicopter relative to the ground.
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The gravity tractor, is a proposed spacecraft that will fly close to an asteroid whose trajectory threatens to impact the Earth. Due to the gravitational attraction between the two objects and a prolonged period of time over which it acts (several years), the asteroid's trajectory is changed slightly, thus hopefully diverting it from impacting the Earth. If the gravity tractor's weight on Earth is 20,000 lbs and it flies with a center of gravity 160ft from the surface of the asteroid, and the asteroid is homogenous pure iron with 1290 ft diameter spherical shape, detirmine the force of mutual attraction. Idealize the gravity tractor to be a particle.
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which two elements define a story's setting?geographical locationcharacter descriptionweather conditionsplot structuredialogue and actionResetNext
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The coefficient of performance (COP) of a refrigerator is defined as the ratio of:________ a) the difference between the heat expelled to the outside from the heat removed from the inside to the work done to remove the heat. b) the heat expelled to the outside to the work done to remove the heat. c) the heat removed from the inside to the heat expelled to the outside. d) the heat removed from the inside to the work done to remove the heat. e) the heat expelled to the outside to the heat removed from the inside.
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a wall, a 55.6 kg painter is standing on a 3.15 m long homogeneous board that is resting on two saw horses. The boards mass is 14.5 kg. The saw horse on the right is 1.00 m from the right. How far away can the painter walk from the saw horse on the right until the board begins to tip?
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A 12.0 V car battery is being used to power the headlights of a car. Each of the two headlights has a power rating of 37.7 Watts. The number of electrons that pass through the car battery each second is ___ x 1019. Assume three significant digits in your answer. You do not need to use scientific notation when you enter your answer.
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A satellite in the shape of a solid sphere of mass 1,900 kg and radius 4.6 m is spinning about an axis through its center of mass. It has a rotation rate of 8.0 rev/s. Two antennas deploy in the plane of rotation extending from the center of mass of the satellite. Each antenna can be approximated as a rod of mass 150.0 kg and length 6.6 m. What is the new rotation rate of the satellite (in rev/s)
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If the archerfish spits its water 30 degrees from the horizontal aiming at an insect 1.2 m above the surface of the water, how fast must the fish spit the water to hit its target? The insect is at the highest point of the trajectory of the spit water. Use g = 10 m/s2.
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A Young's interference experiment is performed with blue-green laser light. The separation between the slits is 0.500 mm, and the screen is located 3.24 m from the slits. The first bright fringe is located 3.30 mm from the center of the interference pattern. What is the wavelength of the laser light?
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The Bohr radius a0 is the most probable distance between the proton and the electron in the Hydrogen atom, when the Hydrogen atom is in the ground state. The value of the Bohr Radius is: 1 a0 = 0.529 angstrom. One angstrom is 10-10 m. What is the magnitude of the electric force between a proton and an electron when they are at a distance of 2.63 Bohr radius away from each other?
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4.A rock is thrown from the edge of the top of a 100 m tall building at some unknown angle above the horizontal. The rock strikes the ground at a horizontal distance of 160 m from the base of the building 5.0 s after being thrown. Determine the speed with which the rock was thrown.
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Three blocks are placed in contact on a horizontal frictionless surface. A constant force of magnitude F is applied to the box of mass M. There is friction between the surfaces of blocks 2M and 3M so the three blocks accelerate together to the right. Which block has the smallest net force acting on it? A) MB) 2M C) 3M D) The net force is the same for all three blocks Submit
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On a distance-versus-time graph, _____. A.) the steeper the slope of the line, the faster the speed of the object B.) if the line has a constant slope, the speed may be changing C.) slope is calculated by dividing the run by the rise D.)if the slope is zero, the object is moving slowly
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What is the energy of a photon with a frequency of 2.2 x 1016 Hz? Planck's constant is 6.63 x 10-34 Jos.O 1.5 x 10-178.8 x 10-17O 1.5 10-16O 8.8 10-16
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Balanced forces can change anobject's direction.A. TrueB. False
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Friction between solids can be most accurately defined as the force thatopposes the sliding motion of two surfaces that are touching each other.A. TrueB. False
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In which direction does the electric field point at a position directly west of anegative charge?A. NorthB. WestO C. EastO D. South
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What is the speed of a bus if itcovers 1.5km in 30 seconds? a. 50km/Hrb. 500m/sc. 50m/sd. 1500m/s
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A girl launches a toy rocket from the ground. The engine experiences an average thrust of 5.26 N. The mass of the engine plus fuel before liftoff is 25.0 g, which includes fuel mass of 12.3 g. The engine fires for a total of 1.90 s.A. What is the average exhaust speed of the engine?B. This engine is placed in a rocket body of mass 60.5 g. What is the magnitude of the final velocity of the rocket if it were to be fired from rest in outer space by an astronaut on a spacewalk?
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