In-class Quiz #4-1 - Free Fall
Can the kinematic equations 1-3 be used to
predict the motion produced by the
acceleration of a mass due to gravity near
the surface of the Earth ?
1. YES
2. NO
In-class Quiz #4-2 – Going Down
A ball of mass 100 kg is dropped from the roof of
a 15 story building-each story is 5.0 m high.
How long does it take to drop 1 story,
2 stories, and 4 stories? (use g= 10 m/s2)
0
1. 1.0, 2.0, and 4.0 sec
1
∆x = vot + at 2
2. 1.0, 4.0, and 16 sec
2
3. 1.4, 2.0, and 4.0 sec
-10
4. 1.0, 1.4, and 2.0 sec
-5.0m=-5t2
t=1.0 s
5. Can not be determined -10.0m=-5t2 t=√2 s
-20.0m=-5t2
t=2.0 s
1