A) How fast was the brick moving after 4s?
Vf=?
Vi=0 (because it was dropped, not thrown)
A= -9.8m/s^2 (gravity)
t= 4s
Use the equation Vf=Vi+A(t)
Vf=0+(-9.8)(4)
Final answer: Vf= -39.2m/s
b) How far did the brick fall after 4s?
D=?
Vi=0
t=4s
A=-9.8m/s2
**You do have the final velocity, but it is best to avoid using numbers that you have calculated yourself.**
Use the equation: d=Vi(t)+0.5(A)(t)^2
d=(0)(4)+0.5(-9.8)(4)^2
d=(-4.9)(16)
d=-78.4m
Therefore, after 4s the brick fell 78.4m
Answer:
Explanation:
Given
Mass of first object 
Mass of second object 
Distance between them 
object is placed between them
So force exerted by
on 



Force exerted by 



So net force on
is



i.e. net force is towards 
(b)For net force to be zero on
, suppose
So force exerted by
and
must be equal








Answer:
because of tungsten's high melting point
Explanation:
Answer:
it depends on the relative masses of the objects.
Explanation: