Answer:
We have to show surface area
,with few conditions that is by considering Force
and Pressure
to be respectively.
Explanation:
The atmospheric pressure is
on Earth's surface.
The magnitude of the force exerted on a person by the atmosphere is
.
Now to calculate surface area we can find it from
and re-arranging it to.

So plugging the values,
Surface area 
Hence from the above calculations we can say that surface area is
.
So the surface area of an average person can be said to have
, using the concept of pressure and force.
Explanation:
If a metal rod of length L moves with velocity v is moving perpendicular to its length, in a magnetic field B, the induced emf is given by :

The electric field in the conductor is given by :

It is clear that the electric field is independent of the length of the rod. If the length of the rod is doubled, the electric field in the rod remains the same.
Answer:
a) 35.94 ms⁻²
b) 65.85 m
Explanation:
Take down the data:
ρ = 1000kg/m3
a) First, we need to establish the total pressure of the water in the tank. Note the that the tanks is closed. It means that the total pressure, Ptot, at the bottom of the tank is the sum of the pressure of the water plus the air trapped between the tank rook and water. In other words:
Ptot = Pgas + Pwater
However, the air is the one influencing the water to move, so elimininating Pwater the equation becomes:
Ptot = Pgas
= 6.46 × 10⁵ Pa
The change in pressure is given by the continuity equation:
ΔP = 1/2ρv²
where v is the velocity of the water as it exits the tank.
Calculating:
6.46 × 10⁵ =1/2 ×1000×v²
solving for v, we get v = 35.94 ms⁻²
b) The Bernoulli's equation will be applicable here.
The water is coming out with the same pressure, therefore, the equation will be:
ΔP = ρgh
6.46 × 10⁵ = 1000 x 9.81 x h
h = 65.85 meters
Answer:
frictonal force due to the surface of irregularities
U=6.9ms-¹
a=0.62ms-²
t=3.4s
V=?
using
v=u+at
v=6.9+(0.62×3.4)
v= 6.9+2.108
v=9.008ms-¹