From what I understand, the word midnight is usually interpreted incorrectly. Midnight is written as 12am which would imply that it's in the morning. Therefore, it should be at the start of the day. On the other hand, both Dictionary.com and the Oxford Dictionary define it as twelve o'clock at night.
James Prescott Joule. The English physicist James Prescott Joule (1818-1889) proved that mechanical and thermal energies are interconvertible on a fixed basis, and thus he established the great principle of conservation of energy.
(jl, joul) The SI derived unit used to measure energy or work. One joule is equal to the energy used to accelerate a body with a mass of one kilogram using one newton of force over a distance of one meter. One joule is also equivalent to one watt-second.