Master Physics with Fun Quizzes & Brain Teasers!

A man stands on a platform that is rotating (without friction) with an angular speed of 1.2 rev/s; his arms are outstretched and he holds a brick in each hand.The rotational inertia of the system consisting of the man, bricks, and platform about the central vertical axis of the platform is 6.0 k g times m squared. If by moving the bricks the man decreases the rotational inertia of the system to 2.0 k g times m squared, what is the resulting angular speed of the platform in rad/s
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You have a fish tank with a square 10 x 10 cm bottom surface. You fill it 9 cm deep with water. What is the force in N on the bottom plate of the tank due to the water (neglect atmospheric pressure)
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A flatbed truck is carrying an 800-kg load of timber that is not tied down. The maximum friction force between the truck bed and the load is 2400 N. What is the greatest acceleration that the truck can have without losing its load
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The hot and neutral wires supplying DC power to a light-rail commuter train carry 700 A and are separated by 70.0 cm. What is the magnitude (in N) of the force between 30.0 m of these wires?
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Calculate the speed of a proton that is accelerated from rest through an electric potential difference of 114 V. m/s (b) Calculate the speed of an electron that is accelerated through the same potential difference. m/s
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The wheels of a skateboard roll without slipping as it accelerates at 0.40 m/s2 down an 85-m-long hill. Part A If the skateboarder travels at 1.8 m/s at the top of the hill, what is the average angular speed of the 2.6-cm-radius wheels during the entire trip down the hill
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what goes up but never comes down i know the answer but do you?
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An optical disk drive in a computer can spin a disk at up to 10,000 rpm. If a particular disk is spun at 5050 rpm while it is being read, and then is allowed to come to rest over 0.435 s, what is the magnitude of the average angular acceleration of the disk?
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In a hydraulic lift, if the pressure exerted on the liquid by one piston is increased by 100 N/m2 , how much additional weight can the other piston slowly lift if its cross sectional area is 25 m2
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You throw a small ball upward and notice the time it takes to come back. If you then throw the same ball so that it takes twice as much time to come back, what is true about the motion of the ball the second time?(a) Its initial speed was twice the speed in the first experiment.(b) It traveled an upward distance that is twice the distance of the original toss.(c) It had twice as much acceleration on the way up as it did the first time.(d) The ball stopped at the highest point and had zero acceleration at that point.
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A 4.5 kg ball swings from a string in a vertical circle such that it has constant sum of kinetic and gravitational potential energy. Ignore any friction forces from the air or in the string. What is the difference in the tension between the lowest and highest points on the circle
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Which energy conversion takes place when a solar cell is used to light a street lamp?
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s it possible for a system to have negative potential energy? Is it possible for a system to have negative potential energy? No, because the kinetic energy of a system must equal its potential energy. Yes, as long as the total energy is positive. Yes, since the choice of the zero of potential energy is arbitrary. No, because this would have no physical meaning. Yes, as long as the kinetic energy is positive.
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A 26 kg child is coasting at 2.0 m/s over flat ground in a 5.0 kg wagon. The child drops a 1.5 kg ball from the side of the wagon. What is the final speed (in m/s) of the child and wagon
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Evaluate (x +y)0 for x= -3 and y=5.0 1201
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If you only 24 hours too live, how would you spend it...
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Which of the following choices correctly identifies the process created by moving a magnet through a conducting loop?a. conductionb. magnetic field generationc. trasformationd. electromagnetic induction
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g The Trans-Alaskan pipeline is 1,300 km long, reaching from Prudhoe Bay to the port of Valdez, and is subject to temperatures ranging from -71C to +35C. How much does the steel pipeline expand due to the difference in temperature?
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Electrons are emitted form a certain metal with a maximum kinetic energy of 2 eV when 6-eV photons are inicident on its surface. What is the maximum kinetic energy of electrons emitted if photons of twice the wavelength are inicdent on this metal? Explain your answer
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what is the answer to [tex]6 + 6 {2}^{2} [/tex]
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Two conducting spheres are each given a charge Q. The radius of the larger sphere is three times greater than that of the smaller sphere. If the electric field just outside of the smaller sphere is E0, then the electric field just outside of the larger sphere is
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Part 3: Problem Set 1. An object is pulled by a rope and dragged to the right 12 meters across a rough surface. The tension in the rope is 105 N and the rope makes an angle of 35 degrees with the horizontal. The rough surface exerts a constant frictional force of 50 N as the object is dragged. 105 N 12 meters a) Find the total amount of work done on the object. Consider the following forces: tension, friction, gravity and normal. b) Use the work energy theorem to find the block's change in kinetic energy.
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A grandfather clock is controlled by a swinging brass pendulum that is 1.2 m long at a temperature of 27C. (a) What is the length of the pendulum rod when the temperature drops to 0.0C? (Round your answer to four significant figures.) mm
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Space vehicles traveling through Earth's radiation belts can intercept a significant number of electrons. The resulting charge buildup can damage electronic components and disrupt operations. Suppose a spherical metallic satellite 1.7 m in diameter accumulates 3.1 C of charge in one orbital revolution. (a) Find the resulting surface charge density. (b) Calculate the magnitude of the electric field just outside the surface of the satellite, due to the surface charge.
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