A physical change in something doesn't change what the it is. For example, if you break glass, it will still be glass. In a chemical change where there is a chemical reaction, a new thing is formed and energy is either given off or absorbed. For example, when you burn a log. The carbon in the log is reacting to the oxygen to create ashe and smoke
Answer:
a) The Energy added should be 484.438 MJ
b) The Kinetic Energy change is -484.438 MJ
c) The Potential Energy change is 968.907 MJ
Explanation:
Let 'm' be the mass of the satellite , 'M'(6× be the mass of earth , 'R'(6400 Km) be the radius of the earth , 'h' be the altitude of the satellite and 'G' (6.67× N/m) be the universal constant of gravitation.
We know that the orbital velocity(v) for a satellite -
v= [(R+h) is the distance of the satellite from the center of the earth ]
Total Energy(E) = Kinetic Energy(KE) + Potential Energy(PE)
For initial conditions ,
h = = 98 km = 98000 m
∴Initial Energy () = m +
Substituting v= in the above equation and simplifying we get,
=
Similarly for final condition,
h= = 198km = 198000 m
∴Final Energy() =
a) The energy that should be added should be the difference in the energy of initial and final states -
∴ ΔE = -
= ( - )
Substituting ,
M = 6 × kg
m = 1036 kg
G = 6.67 ×
R = 6400000 m
= 98000 m
= 198000 m
We get ,
ΔE = 484.438 MJ
b) Change in Kinetic Energy (ΔKE) = m[ - ]
= [ - ]
= -ΔE
= - 484.438 MJ
c) Change in Potential Energy (ΔPE) = GMm[ - ]
= 2ΔE
= 968.907 MJ
Answer:
The range of wavelengths of the sound is 7692.30 m and 3846.15 m
Explanation:
A bat emits pulses of sound at a frequency between 39 kHz and 78 kHz. It is required to find the range of wavelengths of this sound.
Bat uses ultrasonic waves. It moves with the speed of light.
If f = 39 kHz,
If f = 78 kHz,
So, the range of wavelengths of the sound is 7692.30 m and 3846.15 m.