Given information:

Mass of the coal is m=1 kg.

Vertical height is h=100 m.

Calculation:

Refer Appendix II, “Physical constants” for gravitational acceleration value in the textbook.

The value of gravitational acceleration is g=9.8 m/s2.

Find the potential energy associated due to gravitation using the relation:

E=mgh=(1 kg)(9.8 m/s2)(100 m)=980 J

Therefore, the energy associated while dropping the coal is 980 J_.

Given information:

Mass of the coal is m=1 kg.

Calculation:

Let consider the coal contains 100% of carbon.

Refer Equation (1.13) in the textbook.

Combustion of 1 kg of carbon releases energy of E=32.8 MJ.

Convert 32.8 MJ into J:

E=32.8 MJ×106JMJ=3.28×107 J

Therefore, the energy associated while burning the coal is 3.28×107 J_.

Given information:

Mass of the coal is m=1 kg.

Calculation:

Refer Appendix II, “Physical constants” for speed of light value in the textbook.

The value of speed of light is c=3×108 m/s.

Find the energy associated using the relation:

E=mc2=(1 kg)(3×108 m/s)2=9×1016 J

Therefore, the energy associated while converting the mass of the coal into energy is 9×1016 J_.

Compare the energy scale level for the three cases as follows:

The mass of energy while converting the mass (9×1016 J) has higher order of magnitude compared to the energy forms due to dropping and burning.

The energy due to burning (3.28×107 J) is approximately greater than 30, 000 times the energy associated due to gravitation (980 J).