The magnitude of acceleration is (change in speed) / (time for the change).
Change in speed = (speed at the end) - (speed at the beginning) =
(16 m/s) - (0) = 16 m/s .
Time for the change = 4 s .
Magnitude of acceleration = (16 m/s) / (4 s) = 4 m/s per sec = 4 m/s² .
Answer:
(d) Negative.
Explanation:
let's test each at a time.
(a) It can't be 0, because cup would slide back other wise.
(b) Positive, well if forward is positive, than the work done against the forward acceleration must be negative , so it can't be positive.
(c) Equal to non-conservative work done by the car's engine.
well no, because work done by car's engine dosen't go all of it into getting car to move, so it can't be that.
(d) negative, this look like it, because work that friction does must be nagative to counteract positive thrust of car which is positive and in forward direction.
(d) this can't be true.
So the answer is (d) negative.
It increases confidence because the more times you conduct the same experiment over and over should either prove your hypothesis right and wrong and eliminate any random occurrences that might affect your results.
What kind of the question is that. We aren't really buried. We either go to Heaven or the other place. Some people say it's over when your buried in the ground but believers don't really think that.
