Master Physics with Fun Quizzes & Brain Teasers!

Why is electrical energy considered as potential energy as its the energy of moving electrons?
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A physical quantity, G, is defined by G = (Original mass x time)/(change in mass), what is the S.I. unit of G ?
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An actor has a mass of 70 kg. Gravitational field strength = 9.8 N/kg. Use the following equation to calculate the weight of the actor: Weight = mass gravitational field strength. Give your answer to two significant figures.
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what is nuclear energy and light energy by clear explanation
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The velocity of a bus increases by 20 m/s in 80 seconds. What is theacceleration of the bus?A. 0.25 m/s2B. 4 m/s2C. 60 m/s2D. 100 m/s2
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A tissue box has regular dimensionsof 11.8 cm (length), 12.2 cm(width) and 22.5 cm (height).Determine the volume of the tissuebox in cm (V = 1 xwxh)
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How is overgrazing threatening the livelihood of pastoral communities in the savanna in Africa
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Which sentence describes Newton's third law?
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which device conferts electric energy into mechanical energy
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Calculate the momentum of a high-speed"bullet train" with a mass of 9.2 X 108 kgmoving at a speed of 61 m/s.
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A set of electric trains are powered by a 9 V battery. What is the resistance of the trains if they draw 4.0 A of current?
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A spotlight on the ground shines on a wall 12 m away. If a man 2 m tall walks along the x-axis from the spotlight toward the building at a speed of 1.6 m/s, which is taken as the given dx/dt, how fast is the length of his shadow on the building decreasing when he is 4 m from the building
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I pull my child in a sled over the snow. the rope makes an angle with the horizontal so that the pulling force has a horizontal component of 15 n and a vertical component in the upwards direction 25 n . the combined weight of the child and sled is 95 n . i'm getting tired and so the sled is slowing at a constant rate of 0.80 m/s each second.
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When vectors b+a= 5i-j & vectors b-a=i-7j, what is the magnitude and direction of vector a
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The average efficiency of energy transfer between trophic levels is approximately.
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A ball thrown horizontally from the top of a building 24 m above the ground strikes the ground at the distance of 18 m from the base of the building. What was its initial velocity? (Use g = 10 m/s2.)
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Two objects a and b with masses 10.4 kg and 4.6 kg respectively attached to two ends of a light cord that passes a very light, fixed pulley. the system is released from rest so that a and b move vertically. a/ use the energy consideration to find the velocity of a and b after they have moved 1.2 m. b/ compute the tension on each end of the cord.
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One of Newton's laws uses the equation F= ma. Which statement describes.the meaning of this equation? A. Velocity is a change in speed or direction. B. Objects will change motion when unbalanced forces are applied. C. An object can move only if no forces are applied to it. D. It takes more force to move something that has more mass.
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Two plastic balls suspended by strings are placed close to each other. If they have the same charge, how will they interact with each other?
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A water trough is m long and a cross-section has the shape of an isosceles trapezoid that is cm wide at the bottom, cm wide at the top, and has height cm. If the trough is being filled with water at the rate of , how fast is the water level rising when the water is cm deep
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A tourist being chased by an angry bear is running in a straight line toward his car at a speed of 6.96 m/s. The car is a distance d away. The bear is 23.3 m behind the tourist and running at 10.3 m/s. The tourist reaches the car safely. What is the maximum possible value for d
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A car of mass 1000 kg is heading east at 25 m/s. it collides with a car of mass 1200 kg heading north at 30 m/s. when the cars collide, they stick together. a. what is the total momentum of the system before the collision? remember that momentum is a vector quantity, and write the momentum in component notation, with x and y unit vectors. (1 point) b. what is the total momentum of the system after the collision? write the momentum in component notation, with x and y unit vectors. (1 point) c. what is the velocity of the cars after the collision? write the velocity in component notation, with x and y unit vectors. (1 point) d. at what angle do the cars move after the collision? (1 point)
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twice each each lunar month, all year long, these tides occur. whenever the moon, earth and sun are aligned, the gravitational pull of the sun _____ to that of the moon causing _____ tides. a) adds; neap b) adds; maximum c) interferes; neap d) interferes; minimum
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Two arrows are fired simultaneously with the same speed of 30. 0 m/s. Each arrow has a mass of 0. 100 kg. One is fired due east and the other due south. What is the magnitude of the total momentum of this two-arrow system?.
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