Archive for August, 2009
Kinetic Books Physics
How do I make this physics?
A box of books weighing 234 N is pushed through the floor of an apartment by strength of 440 N exerted downward at an angle of 35.5o below the horizontal. If the coefficient of kinetic friction between box and floor is 0519, How long does it take to move the area of 3.16 m, from rest?
All steps in this problem are given with 3 significant digits, so our response must be too. Assuming that the apartment is on Earth, a box weighing 234 N has a mass of 23.878 kilograms (we need it later). The force push can be divided into horizontal and vertical elements: 440 * cos35.5 = 358.21 * horizontal and 440 vertical sin35.5 = 255.51. The vertical component adds the normal force will increase friction: 0,519 * (234 255.51) = 254.05N resistance force due to friction. The difference between the horizontal component of force pushing and resistive force is the net force: 358.21-254.05 = 104.16N. Now the question is when 104.16N net force is applied to a mass of 23.878 kg, how long does it take to move 3.16m? F = ma tells us the acceleration and d = (1 / 2) ^ 2 will be to tell us the time. 104.16 = 23.878 a = 4.3622 a = 3.16 (1 / 2) * (4.3622) * t ^ 2 = 1.4488 t ^ 2 = 1.2037 t round to three significant figures: 1.20 seconds
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The Manga Guide to Physics (Manga Guide to Science) $12.81 Megumi is an all-star athlete, but she’s a failure when it comes to physics class. And she can’t concentrate on her tennis matches when she’s worried about the questions she missed on the big test! Luckily for her, she befriends Ryota, a patient physics geek who uses real-world examples to help her understand classical mechanics-and improve her tennis game in the process! In The Manga Guide to Phy… |
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Physics and the Art of Dance: Understanding Movement $35.49 Physics and the Art of Dance gives all who enjoy dance – whether as dancers, students, teachers, or fans – an opportunity to understand what happens when human bodies move in the remarkable ways we call dance. How, for instance, do dancers create the illusion of defying gravity? Or of starting to spin when in the air with no source of force to act on their bodies? You may observe some dancers u… |
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Energy Medicine in Therapeutics and Human Performance (Energy Medicine in Therapeutics & Human Performance) $45.58 Focusing on the wealth of information emerging in the area of energy medicine, this unique resource explores mechanisms by which mind and body processes influence the body’s healing and performance potential. Content draws on an extraordinary range of sources to explore theories of human energy – from physiology and biophysics, to examples drawn from the realms of “spontaneous healing,” cutting-ed… |