Question

a basketball player jumped straight up to grab a rebound. If she was in the air for .8 second how high did she jump

Answer 1

Answer:
0.78m (rounded to nearest hundredth of a meter)

explanation:
time taken for going up=time taken for drop down after reaching the highest point. at the highest point, the velocity becomes 0.

now all thats left is dropping an object from a height (h) and seeing how long it takes to reach the ground. then find out the flight’s total time divided by 2 (0.8/2=0.4)

lets say the velocity is v and the height she jumped to is h. we can make a kinematic expression:
s=vt+½gt²

once we put it all together you should get this:

h=0×0.4+½(9.81) 0.4²


.
∴
Time taken for downward drop
=
0.8
2
=
0.4
s
Suppose that she jumped with initial velocity
=
u

Also suppose that she jumped to a height
h
Using following kinematic expression
s
=
u
t
+
1
2
g
t
2
and inserting various quantities we get
h
=
0
×
0.4
+
1
2
(
9.81
)
0.4
2

h
=
0.78
m
rounded to nearest hundredth of a meter.