Jaclyn in on an elevator before it begins to move. She pulls out her handy newton force scale and attaches it to the ceiling of the elevator. Next she hangs her 10 kg bag on the scale and notes a reading of 98N, while at rest. When the elevator begins to move the scale suddenly reads 95N. Find and explain the magnitude and direction of the acceleration of the elevator.
2007-03-25 06:06:46 · 2 answers · asked by Anonymous in Science & Mathematics ➔ Physics
I'm not a physics guru, but here is what I think. F = Mass * Accel., right? Okay, so at rest, the bag's force is 98N because all that is affecting it is gravity (9.8 m/s^2). We know that the bag's mass is going to stay the same, so let's find that. Mass = 98N / 9.8 m/s^2... Mass is 10 kg ( I think the units are right). So when the elevator moves, the force is 95N. 95N / 10 kg = 9.5m/s^2. So the acceleration decreases and what does this mean? Well, the elevator should be going up because if it were going down, the accel. should be higher. Not too sure about magnitude.
2007-03-25 06:14:28 · answer #1 · answered by F1reflyfan 4 · 0⤊ 0⤋
Most folks know that when an elevator begins going down, you feel lighter. Ergo, the direction of acceleration is clearly shown to be towqrd the center of the earth.
Before the movement, the 10kg bag experienced a 98 N gravitational force and an equal upward one from the scale. During the acceleration the force is 98 down and 95 up for a net 3N down on a 10kg mass, so
a = 3/10 = .30 m/s² downward
2007-03-25 13:36:58 · answer #2 · answered by Steve 7 · 1⤊ 0⤋