A physics student weighing 500 N stands on a scale in an elevator and records the scale reading over time. The data is
shown in the graph above. At time t= 0, the elevator is at rest on the ground floor.

What is the acceleration of the student
from 10-15 s?

The first law of thermodynamics states that heat added to a system is neither created nor destroyed but is transformed ⇒ as it changes into other forms of energy.

Amachinist turns the power on to a grinding wheel, at rest, at time t = 0 s. the wheel accelerates uniformly for 10 s and reaches the operating angular velocity of 96 rad/s. the wheel is run at that angular velocity for 40 s and then power is shut off. the wheel slows down uniformly at 1.5 rad/s2 until the wheel stops. in this situation, the time interval of deceleration is closest to:

Ain is , is 's of ? 0.62 0.79 1.27 1.50