Question

CAN SOMEONE HELP PLZ

the velocity of an object fired directly upwards given v=96-48t, where t is in seconds. When will the velocity be between 48 and 80 feet per second??

Answer 1

Treat this like 2 separate problems.

1) Find the time at which the vel. is 48 ft/sec:

v = v0 + at is given here and is v = 96-48t (feet/sec)

Set this equal to 48: 48 = 96 - 48t. Divide all terms by 48:

1=2-t = t = 1 sec

2) find the time at which v = 80 ft/sec:

80 = 96-48t => 48t = 16, so t =1/3 sec, or t= 0.33333 ... sec (approx.)


When will the velocity be between 48 and 80 feet per second? Between t=13 sec and t=1 sec (answer)