We Must
ANALYSIS:
One vital concept of physics is the energy. The universe possesses energy and matter. For simplicity, matter is a substance and energy is used to move these substances. Energy is appearing in various forms. Among those are kinetic, gravitational potential, elastic potential, electric potential, thermal, chemical, etc. Work, on the other hand, is the change in energy from one form to another by means of an external force. When work is done on an object, therefore, the object is said to have either gained or lost a certain amount of energy of a particular type. The total work done on a particle by all forces that act on it is equal to the change in its kinetic energy, also known as the work-energy theorem. This can derived from: W=Fdx equation 1 W=maxdx where ax=vdvdx W=mvdvdxdx=mvdv W=v1v2mvdv =12mv22-12mv12 =K2-K1 W=ΔK equation 2 For a body moving along s , displacement with a constant force F, work can be defined as:
W= F . s equation 3
The SI unit for work is J, Joule which is equal to 0.7376 ft.lb in British System.
For instance that F is not parallel to displacement, only the component parallel to the displacement can only affect work. The angle θ between F and s, is related by:
W=Fscosθ equation 4
When force is in the same direction with displacement which is the maximum, work is simply:
W=Fs equation 5 It is related to the magnitude of the vector dot product of force and displacement. Thus, by analysis, for angle θ is 900, force is perpendicular to displacement. Therefore, W=Fscos(900)=0.
On the other hand, Power, which is another term in physics, is the rate of time at which work is done. Power is a function of time unlike in work which is a function of displacement. Similarly, power is also a vector dot product of vectors force and velocity. It is given by the equation:
P=limt→∞ΔWΔt=limt→∞dWdt equation 6
It can be also expressed as:
P=FΔsΔt=Fv
One vital concept of physics is the energy. The universe possesses energy and matter. For simplicity, matter is a substance and energy is used to move these substances. Energy is appearing in various forms. Among those are kinetic, gravitational potential, elastic potential, electric potential, thermal, chemical, etc. Work, on the other hand, is the change in energy from one form to another by means of an external force. When work is done on an object, therefore, the object is said to have either gained or lost a certain amount of energy of a particular type. The total work done on a particle by all forces that act on it is equal to the change in its kinetic energy, also known as the work-energy theorem. This can derived from: W=Fdx equation 1 W=maxdx where ax=vdvdx W=mvdvdxdx=mvdv W=v1v2mvdv =12mv22-12mv12 =K2-K1 W=ΔK equation 2 For a body moving along s , displacement with a constant force F, work can be defined as:
W= F . s equation 3
The SI unit for work is J, Joule which is equal to 0.7376 ft.lb in British System.
For instance that F is not parallel to displacement, only the component parallel to the displacement can only affect work. The angle θ between F and s, is related by:
W=Fscosθ equation 4
When force is in the same direction with displacement which is the maximum, work is simply:
W=Fs equation 5 It is related to the magnitude of the vector dot product of force and displacement. Thus, by analysis, for angle θ is 900, force is perpendicular to displacement. Therefore, W=Fscos(900)=0.
On the other hand, Power, which is another term in physics, is the rate of time at which work is done. Power is a function of time unlike in work which is a function of displacement. Similarly, power is also a vector dot product of vectors force and velocity. It is given by the equation:
P=limt→∞ΔWΔt=limt→∞dWdt equation 6
It can be also expressed as:
P=FΔsΔt=Fv