* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download Raising and Lowering
Survey
Document related concepts
Equivalence principle wikipedia , lookup
Mechanics of planar particle motion wikipedia , lookup
Woodward effect wikipedia , lookup
Centrifugal force wikipedia , lookup
Lorentz force wikipedia , lookup
Coriolis force wikipedia , lookup
Pioneer anomaly wikipedia , lookup
Artificial gravity wikipedia , lookup
Modified Newtonian dynamics wikipedia , lookup
Velocity-addition formula wikipedia , lookup
Fictitious force wikipedia , lookup
Transcript
Raising and Lowering 1 1 2 A box is lowered at constant velocity. Does the acceleration depend on the velocity? What is the net force on the box? Draw a force diagram for the box. Acceleration = rate of change in velocity = 0 for any size constant velocity (5 – 5 = 0, 10 – 10 = 0, etc.) The net force = mass x acceleration = 0 velocity FT Acceleration = 0 mg 3 2 4 A box is raised at constant velocity. Is the acceleration +, -, or 0? What is the net force on the box? Draw a force diagram for the box. Acceleration = rate of change in velocity = 0 since velocity does not change The net force = mass x acceleration = 0 velocity FT Acceleration = 0 mg 5 3 6 A box is lowered with uniformly increasing speed and more negative velocity. Is the acceleration +, -, or 0? Is the net force on the box, up, down or zero? Draw a force diagram for the box. Acceleration is (-) since the velocity is becoming more negative The net force = mass x acceleration which is downwards since acceleration is downwards. FT acceleration velocity mg 7 4 8 A box is raised with uniformly increasing speed and more positive velocity. Does the acceleration depend on the velocity? Is the net force on the box, up, down or zero? Draw a force diagram for the box. Acceleration is (+) since the velocity is becoming more positive The net force = mass x acceleration which is upwards since acceleration is upwards. FT acceleration velocity mg 9 5 10 A box is lowered with uniformly decreasing speed and less negative velocity. Draw a motion diagram for the box. Is the net force on the box, up, down or zero? Draw a force diagram for the box. Acceleration is positive, e.g. velocity might change from -10 to -5, an increase of +5. The net force = mass x acceleration which is upwards since acceleration is upwards. acceleration It takes a net upward force to slow the descent of the box. velocity FT mg 11 6 12 A box is raised with uniformly decreasing speed and less positive velocity. Draw a motion diagram for the box. Is the net force on the box, up, down or zero? Draw a force diagram for the box. Acceleration is negative, e.g. velocity might change from +10 to +5, a change of -5. The net force = mass x acceleration which is downwards since acceleration is downwards. FT acceleration mg velocity 13