Answer: 1.39 s
Explanation:
We can solve this problem with the following equations:
(1)
(2)
Where:
is the length the steel wire streches (taking into account 1mm=0.001 m)
is the length of the steel wire before being streched
is the force due gravity (the weight) acting on the pendulum with mass 
is the transversal area of the wire
is the Young modulus for steel
is the period of the pendulum
is the acceleration due gravity
Knowing this, let's begin by finding :
(3)
Where 
is the diameter of the wire
(4)
(5)
Knowing this area we can isolate from (1):
(6)
And substitute in (2):
(7)
(8)
Finally:
Answer:
She should drop two balls with different masses from the same height
Explanation:
Answer:
Given
mass (m) =2kg
velocity (v) =3m/s
momentum (p) =?
Form
p=mv
2kgx3m/s
p=6kg.m/s
the momentum of ball's =6kg.m/s
Mass is the physical quantity
