Acceleration Problems and Graphs More Problems How fast

Acceleration Problems and Graphs

More Problems How fast is that book going when it hits the ground? (remember don’t use your rounded answer, save the # in your calculator) a = (vf-vi)/t 9. 8 = (vf-0)/5. 5328333517 vf = 54 m/s Which probably means that student is going to have some fees at the end of the year.

Still more problems After thinking of the fees he will have to pay, the same Physics student angrily throws his calculator at the book with a velocity of 11 m/s, how long will it take for the calculator to hit? (its is still a 150 m high building) d = vit + ½ gt 2 150 = 11 t +. 5(9. 8)t 2 use the quadratic formula t= 4. 5 s or – 6. 8 s negative times aren’t possible!

Vertical Leap The NBA player with the highest vertical leap (Wilt Chamberlain) could jump with an initial velocity of 4. 9 m/s up. How long did he stay in the air? Draw the motion map an to aide in this problem Displacement for this problem is 0 m, and final velocity is -4. 9 m/s

2 different ways to get the answer d = vit + ½ at 2 0 = 4. 9 t + ½ (-9. 8)t 2 0 = t (4. 9 + ½ (-9. 8)t) So eithther t = 0 or 0= ½ (-9. 8)t A 0 time won’t work for this so… t = 1. 0 sec or a = (vf – vi)/t -9. 8 = (-4. 9)/ t t = 1. 0 sec

Draw all 3 graphs for this motion displacement vs. time

Draw all 3 graphs for this motion velocity vs. time

Draw all 3 graphs for this motion Acceleration vs. time

How high could he jump? how high could Wilt Chamberlain jump? vi = 4. 9 m/s you must determine that he will reach his maximum height at the midpoint of his jump, or half the time 1. 0 s / 2 =. 50 s d = 4. 9 m/s (. 50) + ½ (-9. 8). 50 s 2 d = 1. 2 m