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What will be the kinetic energy of a body when its mass is made 4 times and velocity is doubled |
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Answer» YOUR ANS ...Kinetic Energy = 1/2 mv^2Numbers are generally better for comparison than variables, so I’m going to assign a few.m = 1, v = 1Therefore KE_original = 1/2 * 1 * 1^2 = 1/2(It’s against my better judgment, but I’ll leave them unitless. Don’t leave numbers unitless unless they’re meant to be. UNITS make everything better. )If the mass is quadrupled, then the new mass is 4. If the velocity is DOUBLED, then the new velocity is 2. LET’s do the math.KE_new = 1/2 * 4 * 2^2 = 8 = 16 * KE_originalLet’s think about this…Energy is directly proportional to mass:QUADRUPLE the mass → quadruple the energyEnergy is directly proportional to velocity squared:Double the velocity → quadruple the energyWith a factor of 4 from both relevant variables, it makes sense that the new energy is 16x the original.HOPE IR WRKS |
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