Answer:

Explanation:
As we know that velocity as a function of position is given as

now in order to find the acceleration we can use that rate of change in velocity is known as acceleration
So we will have




Now by Newton's 2nd law we have


For free falling bodies, the final velocity may be calculated through the equation,
Vf = gt
Where g is the acceleration due to gravity (9.8 m/s²) and t is the time elapsed. Substituting the known values,
Vf = (9.8 m/s²) x (4 s) = 39.2 m/s
Therefore, the object's velocity is approximately 39.2 m/s.
<span>The
temperature at which the vapor pressure of a liquid equals the
environmental pressure surrounding the liquid is best defined as:
Boling Point
</span>
Answer:
Electric flux, 
Explanation:
It is given that,
Electric field, 
We need to find the electric flux through a circular area of radius 2.66 m that lies in the xy-plane. 
The electric flux is given by :


Since, k.k=i.i=j.j = 1
So,


So, the electric flux through a circular area is
.Hence, this is the required solution.
Answer:
Explanation:
See the attached figure . See the forces acting on man pulling up the box .
Man is stationary so net force acting on man is zero .
T + R = Wman
R is the reaction force of the ground of second floor .
R = Wman - T