What is the kinetic energy (in J) of a body moving at ?
Answer and explanation
Correct answer: D. 20
**
- Step 1: Kinetic energy is defined as .
- Step 2: Setting and , write .
- Step 3: The calculated energy is .
Answer
20.
Why not the others: '80' multiplies by instead of dividing by , calculating ; '40' omits the factor of , calculating ; '10' forgets to square the velocity, calculating .
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