An elevator of mass 500 kg is caused to accelerate upward at 3.0 m/s² by a force in the cable. What is the force exerted by the cable? A) 1,500 N B) 4,900 N C) 6,400 N D) 2,900 N E) zero

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We can use Newton's Second Law which states that force is equal to mass times acceleration (F=ma). In this case, the force we are looking for is the force exerted by the cable, the mass is 500 kg (given), and the acceleration is 3.0 m/s^2 (given). Therefore, F = 500 kg x 3.0 m/s^2 = 1,500 N. So, the answer is not A. However, we need to remember that the elevator is going upward, which means the force exerted by the cable must be greater than the weight of the elevator (mass x gravity). The weight of the elevator is 500 kg x 9.8 m/s^2 = 4,900 N. So, the force exerted by the cable must be equal to the sum of the weight of the elevator (4,900 N) and the force required to accelerate it upward (1,500 N). Therefore, the total force exerted by the cable is 4,900 N + 1,500 N = 6,400 N. So, the correct answer is C. The elevator is not at rest, so the answer cannot be E. The other choices are incorrect based on the calculations above.

An Elevator of Mass 500 Kg Is Caused to Accelerate