A2.00 kg block hangs from a spring balance calibrated in newtons that is attached to the ceiling of an elevator. (a) what does the balance read when the elevator is ascending with a constant speed of 34 m/s? (b) what does the balance read when the elevator is descending with a constant speed of 27 m/s? (c) what does the balance read when the elevator is ascending at 33 m/s and gaining speed at a rate of 9 m/s^2? (d) suppose that from t = 0 to t = 4.6 s, the elevator ascends at a constant speed of 10 m/s. its speed is then steadily reduced to zero during the next 3.5 s, so that it is at rest at t = 8.1 s. describe the reading of the scale during the interval 0 < t < 8.1 s.

The correct choice is c

Answertraveling around a circular trackexplanation"traveling around a circular track" is the best answer as you could be traveling around a circular track at a constant speed. your velocity would therefore have the same magnitude but will always be constantly direction. since acceleration is the rate of change of velocity, the rate of change will only involve the direction of velocity and not the magnitude.wrong choices: "an object at rest" does not accelerate at all"increasing speed while traveling around a curve" means that the acceleration will not be constant due to only change in direction; it will be constant due to both magnitude and direction"an object in free fall" does not necessarily change direction 

You need to calculate the string in between two masses