A mass m is suspended from a string attached to the ceiling of an elevator. The elevator has acceleration "a" upward. The tension in the string is:
Correct answer: D. m g + ma
- A. m a
- B. m g
- C. m g - m a
- D. m g + ma
Explanation
In this question, the key concept is to recognize the forces acting on the mass in the elevator. The tension in the string can be calculated by considering the net force, which is the difference between the tension and the gravitational force, equal to mass times acceleration (F net = m a).By rearranging the equation T - m g = m a, we find that T = m g + m a. This means that the tension in the string is the sum of the gravitational force and the product of mass and acceleration.Options A, B, and C are incorrect as they do not correctly represent the relationship between tension, gravitational force, mass, and acceleration.
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