Physics
Work, Energy and Power
Mechanical Energy
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⚡ Quick Summary
Mechanical energy is the sum of kinetic and potential energy of a system.
Mechanical Energy = Kinetic Energy + Potential Energy
The kinetic energy and the potential energy of a system, taken together, form mechanical energy.
Internal/Thermal Energy
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Internal energy (or thermal energy) refers to the total energy related to the internal motion and interactions of molecules within a body.
N/A
The total energy corresponding to the internal motion of molecules and their interaction is called internal energy or thermal energy of the body.
Mass-Energy Equivalence
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Mass and energy are equivalent and interconvertible, as described by Einstein's equation.
E = mc^2
Einstein’s special theory of relativity shows that a material particle itself is a form of energy. The ralation between the mass of a particle m and its equivalent energy E is given as E = mc^2, where c = 3 * 10^8 m/s is the speed of light in vacuum.
Law of Conservation of Energy
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Energy cannot be created or destroyed, but it can be transformed from one form to another.
N/A
Energy can never be created or destroyed, it can only be changed from one form into another.
Block released from compressed spring
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Determining the velocity of a block as a function of its distance from a wall after being released from a compressed spring.
None explicitly provided in the extract, but the solution would involve using Conservation of Energy and the formula for elastic potential energy: U = (1/2)kx^2
The block is pushed by the spring until the spring reaches its natural length. Apply conservation of energy to find the velocity as a function of distance.
Work and Energy
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⚡ Quick Summary
The concepts of work, kinetic energy, potential energy, and the conservation of energy.
Work Done = Force x Displacement x cos(θ); Kinetic Energy = (1/2)mv^2; Potential Energy (Gravitational) = mgh
Explains the relationship between force, displacement, and energy transfer. Includes conservative and non-conservative forces.