Answer:
Net forces which pushes the window is 30342.78 N.
Explanation:
Given:
Dimension of the office window.
Length of the window =
m
Width of the window =
m
Area of the window = 
Difference in air pressure = Inside pressure - Outside pressure
=
atm =
atm
Conversion of the pressure in its SI unit.
⇒
atm =
Pa
⇒
atm =
Pa
We have to find the net force.
We know,
⇒ Pressure = Force/Area
⇒ 
⇒ 
⇒ Plugging the values.
⇒
⇒
Newton (N)
So,
The net forces which pushes the window is 30342.78 N.
Answer:
4 m/s
Explanation:
m1 = m2 = m
u1 = 20 m/s, u2 = - 12 m/s
Let the speed of composite body is v after the collision.
Use the conservation of momentum
Momentum before collision = momentum after collision
m1 x u1 + m2 x u2 = (m1 + m2) x v
m x 20 - m x 12 = (m + m) x v
20 - 12 = 2 v
8 = 2 v
v = 4 m/s
Thus, the speed of teh composite body is 4 m/s.
Answer:
W = 0 J
Explanation:
The amount of work done by gas at constant pressure is given by the following formula:

where,
W = Work done by the gas
P = Pressure of the gas
ΔV = Change in the volume of the gas
Since the volume of the gas is constant. Therefore, there is no change in the volume of the gas:

<u>W = 0 J</u>
The force pushing down is the force of Gravity. On a chair it is in perfect balance with the force pushing up (the normal force)
in terms of magnitude
FN = FG = mg
the forces are in opposite direction
hope this helps