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Reading/Study GuideRead Conceptual Physics – Chapter 7 Answer the following questions1. Impulse is a quantity that changes something’s _____time_____. Work is the effortexerted on something that will change its ____energy____. Work is the product ofthe force times the ___distance______ traveled. (Section 7.1)2. Energy stored by virtue of its position is called ____potential____ Energy.Gravitational potential energy possessed by an elevated object is equal to theweight of the object times its _______height___. This energy is equal to the workdone in lifting it. Only the change of potential energy has meaning. (Section 7.2)3. The kinetic energy of a moving object is equal to ½ times its mass times thesquare of the ______speed____. (Section 7.3)4. Work must be done on an object to _____increase_____ its speed. The change inits kinetic energy is equal to the work done on the object. This is thework-energy theorem. Work is not a form of energy but a way of_______transferring______it. (Section 7.4)5. Energy cannot be created or _____destroyed___, but only transferred from oneform to another. This is the law of conservation of energy (Section 7.5)6. A machine is a device that multiplies ______force__or changes its direction. Alever is a force multiplier, but not a work or energy multiplier. A pulley changesthe _______direction____ of a force, but in the right configuration can be a forcemultiplier (Section 7.6)7. When energy is transferred there is some ______dissipated____. Efficiency is theratio of the useful energy output divided by the total energy input. It would benice to have an engine at 100% efficiency, but this is _____impossible______.(Section 7.7)8. The sun is practically the source of all our __energy____ except nuclear power.Hydrogen is the least ____polluting___ of all fuels. Nuclear fuels are the most____concentrated_______ source of usable energy. (Section 7.8)Watch Work and Energy #28 athttp://www.conceptualphysics.com/21-30.html Answer the followingquestion:9. Answer Paul’s Final question: “How much energy would be needed to pushedthe block of ice up the ramp shown if the block weighed 500 N?” Show yourwork. W= 500N x 6 m= 3,000 JHe would need 3,000 joules of energy to push it up.Read Conceptual Physics – Chapter 8 Answer the following questions10.The linear speed of something moving along a circular track is called____rotational____ speed. Rotational speed is the number of rotations orrevolutions in a given unit of _time_. Tangential speed is the product of theradius times the rotational speed. (Section 8.1)11.The property of a body to resist changes in its rotation is called rotational___inertia___. Rotational inertia causes a rotating body to tend to remainrotating, and non-rotating bodies to remain ____at rest________. (8.2)12.Torque is the counterpart of __force__. A torque causes things to twist orchange their rotational motion. A torque is created by a force applied adistance from a rotational axis. This distance is called the ___lever arm______.(Section 8.3)13.If you toss an object into the air, it will rotate (or wobble) around a special pointcalled the _______center of gravity_____. The center of mass of an object is theaverage position of all of its mass. The center of gravity of an object refers tothe same point as the center of mass. (Section 8.4)14.Any force directed toward a fixed center is called a _____centripetal____ force.This is not a basic force of nature; it is simply the name given to a force directedtoward the center. These forces might be string tension, ____gravitational____,_____electrical_____, or other. (Section 8.5)15.An apparent outward force felt by a rotating occupant that seems to be outwardis called a ______centrifugal____ force. This force does not have an agent but issimply due to the rotation of the object. It is often called an inertial force or a________apparent ____ force. To a person experiencing this, it can seem very real.(Section 8.6)16.An object of mass m moving with a velocity v has a linear momentum m*v. Anobject that is rotating has an angular momentum given by its rotational inertialtimes its rotational ______velocity_____. An object will maintain its angularmomentum unless acted upon by an external net _torque________. (Section 8.7)17.If no external torque acts on a rotating system, the angular momentum remains______constant____. (Section 8.8)Watch Angular Movement #43 athttp://www.conceptualphysics.com/41-50.html Answer the following question:18. Answer Paul’s Final question: What happens to your rotation when you crawlfrom the center of a spinning merry-go-round. What principle explains youranswer. Just as when he was on the spinning table and moved his arms out and itslowed him down, when you move towards the outside of the merry-go-round youwould also slow down. This is because the angular momentum is changed. Theangular momentum isn’t constant anymore because you (the external net torque)shifted your weigh to the outside of the

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