If momentum is increased by 20% then K.E. increase by :
Correct answer: A. 0.44
- A. 0.44
- B. 0.55
- C. 0.66
- D. 0.77
Explanation
If momentum is increased by 20%, then the kinetic energy increases by 44% or 0.44 The kinetic energy of an object is given by the equation KE = 1/2mv2, where KE is the kinetic energy, m is the mass of the object, and v is the velocity of the object. The momentum of an object is given by the equation p = mv, where p is the momentum, m is the mass of the object, and v is the velocity of the object. If the momentum is increased by 20%, then the new momentum is 1.2 times the old momentum. Therefore, p2 = 1.2p1. Using the equations for momentum and kinetic energy, we can derive the following equation: KE2 = 1/2m(v2)2 = 1/2m[(p2/m)2/m2] = 1/2(p22/m2). Substituting p2 = 1.2p1, we get KE2 = 1/2[(1.2p1)2/m2] = 1.44(1/2)(p12/m2) = 1.44KE1. Therefore, if momentum is increased by 20%, then the kinetic energy increases by 44%
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About Kinetic Energy
Kinetic energy is the energy of motion, given for a nonrelativistic object by K = ½mv², so it depends on mass and the square of speed. Questions connect kinetic energy with work through the work energy theorem, calculate changes in kinetic energy, and distinguish it from momentum and potential energy.
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