How do I compare Newtons first, second , and third law with tennis?
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1st law objects at rest tend to stay at rest and objects in motion stay in motion with the same speed and direction unless acted upon by an un balanced force.\nThe tennis ball at you feet will stay on the ground at rest unless an unbalanced force occurs, such as high wind.\nThe ball you volley will travel in the direction you hit at a constant speed at direction if the unbalanced forces did not interfer. (gravity wind, the other player returning it)\n\n2 the force of an object is equal to its mass times its acceleration. your tennis ball can be hit with tremendoius force, or lobbed more gently, the mass of the ball has not changed, but the acceleration has and so the force of the object varies.\n\n3 For every action, there is an equal and opposite reaction." Ok lets toss a ball up and overhand serve it.\nthe ball meets the racket. If you could slow motion the whole thing you  would see a moving ball and a moving racket. when they make contact the ball moves in the direction it was hit.  You could see the strings of the racket react to the force of the ball, you can feel the "shock" of the rackets travel being acted on by the ball.\nthe ball reacts with travel based on the force with which the racket interacts with it, the racket seems little moved by the hit but in fact we know it has asorbed the impact and transfers it down your hand, wrist, arm. The greater the force of the racket the more it's path is interupted and the more you Feel the hit. The ball also reacts in equal part with traveling with greater or lesser force. The racket does not travel off at the same speed and manner as the ball,why? F=M*A the mass of the racket in your hand is greater than the ball.\n\ncan you figure out how this applies to a returned volley?\n\nof course we are subject to unbalanced forces playing tennis. gravity is one of them, wind can be another. How windy coes it have to be to take a toll on your game? what about the court surface being wet? can you  think of any other forces? why does the ball drop rapidly after some hits?
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A force is a push or pull on an object.\n\nNewton's second law states that a an applied force causes an object to accelerate.  It's one of the most if not the most powerful physics equations.  Force equals mass times acceleration.  F=ma.  So when an object falls the force of an object is equal to the mass of the object times the acceleration due to Earth's gravity (9.81 m/s/s or 9.81 meters per second per second or meters per second squared.)  All objects experience the same acceleration due to gravity.  The units for force are, oddly enough, called Newtons and one newton equals one kilogram times one meter per second squared.  One pound is 4.48 newtons. \n\nNow it's important to understand that newton's second law, F=ma, applies to net forces or unbalanced forces.  Just because an object is moving doesn't mean it's accelerating.  When you press the accelerator you car speeds up and the engine is exerting a net force on the car.  When your speed maxes out at 120 or however fast your car can go the force of the engine is ballanced against the forces against the car (friction from air, the road and the engine parts)  \n\nTake tug of war.  An set of even matched teams won't result in one team moving across the line.  The forces are balanced.  Add one more strong guy to one team and the weaker team will speed up from zero to slowly moving across the line.  \n\nAlso force is cumulative.  When you can't pick up a heavy box what do you do?  You get help.  One smurf can lift a pebble but the whole smurf village can lift a boulder.\n\nAlso acceration is velocity divided by time a velocity is different from speed in that velocity is a vector, it has magnitude (speed) and direction.  If you change directions you will accelerate.\n\nIf you're in a train with no windows and an increadibly smooth track you shouldn't be able to tell that you are moving if the train't velocity is constant, however if it speeds up, slows down or goes around a corner while going at a constant speed the velocity is changing.  In the first two cases because of a change in magnitude (speed) in the last case because of a change in direction and you experience a force that pushes or pulls you in a direction.\n\nWeight is the force due to gravity and can change due to the masses of the objects involved.  For example you may have a weight of 100 lbs on earth and a mass of 40 some kilograms but on the moon you weigh 1/6 as much but still have a mass of 40 kg.  On Earth you can convert between pounds (a measure of force) and kilograms (a measure of mass) because the acceleration due to Earth's gravity (9.81 meters per second squared) is the same and cancels out in the equation.
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This is not Newtons third law. the two forces you mentioned does not form action reaction pair. they act on the same body. Newtons third law in this case is : action : force of gravity exerted by the earth on the book , reaction : force of gravity on earth by the book. and action : normal force on the book by the table , reaction : force exerted by the book on the table in the downward direction
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Newton's First Law of Motion:\n 1. Every object in a state of uniform motion tends to remain in that state of motion unless an external force is applied to it.  \n\nNewton's Second Law of Motion:\n 2. The relationship between an object's mass m, its acceleration a, and the applied force F is F = ma. Acceleration and force are vectors (as indicated by their symbols being displayed in slant bold font); in this law the direction of the force vector is the same as the direction of the acceleration vector.  \n\nNewton's Third Law of Motion:\n 3. For every action there is an equal and opposite reaction.
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Force = 60 N.\nMass = 3 kg\nTime = 10 s\n\nAn object's change in momentum, Δp equals the Impulse, I on the object. I = ∫F dt = Ft. \n\nΔp = I = Ft = (60 N) * 10 s = 600 Ns\n\nAssuming the object started at rest,\np (initial) = mv = (3 kg) (0 m/s) = 0 Ns\nΔp = 600 Ns\np (final) = 600 Ns\n\np (final) = mv = (3 kg) * v(final)\nv(final) = (600 Ns) / (3 kg) = 200 m/s\nΔv = v(final) - v (initial) = 200 m/s - 0 m/s = 200 m/s\n\nThe object's change in momentum was 600 Ns (kg * m/s).\nThe object's change in velocity, assuming it started from rest, was 200 m/s.
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Two\n\nWeigh ABC against DEF\n\nIf the balance tilts, take the lighter group and weigh one ball against a second one. If it tilts take the lighter ball, If it doesn't tilt, it must be the third ball of that group of 3 balls.\n\nIf ABC weigh the same as DEF, weigh G against H, take the lighter one if it tilts. take I if G and H weigh the same as one another.\n\nTwo weighings suffice.
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Momentum - P = mv (P=momentum, m=mass, v = velocity)\nThree Laws of Newton - F = ma (F=Force; a=acceleration)\nEquations of motion - 1) v = u + at\n                                    2) S = (1/2)ut + at^2\n                                    3) v^2 = u^2 + 2aS\n(v=final velocity; u = initial velocity; S=distance)\n\nIf this can help you please mail me back !\nBEST OF LUCK !!!!
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Force = mass x acceleration\n Mass = weight times gravity\nAcceleration is speed/time\n example if I’m playing football and I want to move the other player assuming we are both on the same planet (gravity is constant) and we are both moving at the same speed at each other I can do so if am heavier than him (increase wt (g) = increase mass) or I decease the time it takes to reach that player (constant speed and distance in less time = acceleration) or I can do both. This is how you increase force by increasing acceleration, mass, or both
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This is really simple stuff. Newtons is force, seconds is time, meters is length, and meters per second is length per time, or velocity.
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All three Newton laws are real. They do support other two law, there is no conflict in them.
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Read Newton's 3rd law of motion.\nAlso, use F=ma to figure out your acceleration.
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Assume that the cue ball has mass m and initial velocity v, and that after the collision, the cue ball has velocity v1 at an angle of x to its original path, and the 8 ball has velocity v2.\n\nx-direction: p1 = p2: mv = mv2 cos 35 + mv1 cos x\ny-direction: p1 = p2: 0 = v2 sin 35 - v1 sin x\n\nv = v2 cos 35 + v1 cos x\nv1 = v2 sin 35 / sin x\n\nv = v2 cos 35 + v2 sin 35 cot x\n\nKinetic energy: 1/2 mv^2 = 1/2 m (v1^2 + v2^2)\nv^2 = v1^2 + v2^2\n\n(v2 cos 35 + v2 sin 35 cot x)^2 = (v2 sin 35 / sin x)^2 + v2^2\n\n(cos 35 + sin 35 cot x)^2 = (sin 35 csc x)^2 + 1\n\ncos^2 35 + (2 cos 35 sin 35) cot x + (sin ^2 35) cot^2 x = (sin^2 35) csc^2 x + 1\n\ncos^2 35 + (2 cos 35 sin 35) cot x = (sin^2 35)( csc^2 x - cot^2 x) + 1\n\n[Remember that 1 + cot^2 x = csc^2 x]\n\ncos^2 35 + (2 cos 35 sin 35) cot x = (sin^2 35)( 1) + 1\n\n(2 cos 35 sin 35) cot x = sin^2 35 + (1 - cos^2 35)\n\n(2 cos 35 sin 35) cot x =  2 sin^2 35\n\ncot x = 2 sin^2 35 / (2 cos 35 sin 35) = tan 35 = cot 55\n\nx = 55 degrees\n\nThanks for giving me something to do.
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Newton's third law: law of reciprocal actions\n \nAll forces occur in pairs, and these two forces are equal in magnitude and opposite in direction. \n\n\nThe third law follows mathematically from the law of conservation of momentum.
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http://en.wikipedia.org/wiki/Newton%27s_law_of_universal_gravitation
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There is a great website on this kind of stuff, check out:\n http://scienceworld.wolfram.com/physics/NewtonsLawofCooling.html\n\nThere is also an equivalent one for mathematics:\n\nhttp://mathworld.wolfram.com/\n\nExcellent resources for basic to advanced theory.
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Newtons 3 laws of motion say:\n1) An object at rest tends to stay at rest and an object in motion tends to stay in motion with the same speed and in the same direction unless acted upon by an unbalanced force.\n2)F=MA or force = mass times acceleration. It describes how an unbalanced force acts in the first law. THIS IS THE MOST IMPORTANT DISCOVERY IN ALL THE HISTORY OF SCIENCE!!!!!\n3) For every action, there is an equal and opposite reaction.\n\nNewton also discovered that gravity is a force of attraction between two masses that is equal to the product of the two masses times the gravitational constant divided by the square of the distance between them. Or F=GMm/R^2.\n\nThe combination of all of the above explains all orbits, rocket propulsion, life the universe and everything!\n\n\nThen Einstein comes along and messes it all up. He says that there is a small error in Newton's laws that depends on the speed. For stuff going really fast, Newtons laws are just totally wrong. Gravity isn't even a force at all, it is a curvature in space time.\n\nBut for every day applications, like designing a 747 or computing the path of an artillery shell or a zillion other things, Newtons laws are still used as is because the errors are vanishingly small under normal conditions.
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Try this: http://en.wikipedia.org/wiki/Newton's_method