Suppose an automobile has 2100 J of kinetic energy. When it moves at twice the speed, what will be its kinetic?
Reaga asked:
Suppose an automobile has 2100 J of kinetic energy. When it moves at twice the speed, what will be its kinetic energy?
8400 J
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Suppose an automobile has 2100 J of kinetic energy. When it moves at twice the speed, what will be its kinetic energy?
8400 J
What’s its kinetic energy at three times the speed?
____?
March 14th, 2010 at 3:46 pm
18900 J
KE = 1/2 * m * v^2
Since Kinetic Energy is directly proportional to the velocity squared, if you travel 2x as fast, you have 4x the kinetic energy. 3x as fast would be 9x KE; 4x as fast would be 16x KE…and so on.
So your solution to 3x the speed would be 9x the KE. Therefore, KE = 9 * 2100 = 18900 J thebody44
March 15th, 2010 at 10:59 pm
1/2(m)v^2=2100
1/2(m)(2v)^2=4×2100=8400 joules,m will NOT change much.
God bless you. nozar nazari