Answer
Pressure, P = 1 atm
air density, ρ = 1.3 kg/m³
a) height of the atmosphere when the density is constant
Pressure at sea level = 1 atm = 101300 Pa
we know
P = ρ g h


h = 7951.33 m
height of the atmosphere will be equal to 7951.33 m
b) when air density decreased linearly to zero.
at x = 0 air density = 0
at x= h ρ_l = ρ_sl
assuming density is zero at x - distance

now, Pressure at depth x


integrating both side


now,


h = 15902.67 m
height of the atmosphere is equal to 15902.67 m.
1.358 J is the kinetic energy of the car driven by Mrs. Waid.
<u>Explanation:</u>
Given data:
Velocity at which Mrs. Waid drives her car = 80 mph
In order to convert mph (meter per hour) into mps (meter per second),

Car weighs 2500 lbs, means mass of the car, m = 2500 lbs
I kilo gram = 2.20462 pound
Therefore, 1 pound (lb)= 0.45359237 kilograms (kg).
To converting pounds into kilogram,

As we know, the kinetic energy can be defined as directly proportionate to the object’s mass (m) and square of its velocity (v). The expression can be given as below,

By substituting the given values, we get



Kinetic Energy because when the pendulum is dropped its gravitational energy is transferred into kinetic energy as it gains speed.