Please explain in detail how you came to the answer, and what concepts you used
ID: 1369381 • Letter: P
Question
Please explain in detail how you came to the answer, and what concepts you used to come upon it.
1) A baby swing is rocking in the wind, and has an angular frequency =3rad/s. What would happen to the angular frequency if you placed a baby in the swing?
a) (baby) > empy b) (baby) = (empty)
c) (baby) < (empty d) not enough information
2) A large building in Oklahoma starts swaying wildly from side to side even during very small earthquakes. What can be done to lessen the amount of swaying?
a) Add a large mass to the top of the building
b) Add more supports to stifffen the building
c) Either A or B
d) Neither A nor B
Explanation / Answer
Here ,
1)
as the angular frequency is inversely proporational to moment of inertia .
when baby is placed , moment of inertia will increase
hence , the correct option is c) (baby) < (empty
2)
as for reducing the swaying the building ,
we can increase a intertia of bulding ,
stiffening the supports make cause them to break under stress
hence ,
a) Add a large mass to the top of the building