Engineering in Kenya

Energy in Electrical Engineering in Kenya

Posted by on Apr 14, 2018 in Physics | 0 comments


For Electrical Engineering in Kenya, energy is defined as the capacity to do work. An object may have mechanical energy by virtue of its position, internal structure or its motion. There are also other forms of energy save for mechanical, namely: chemical energy (found in foods, oils, charcoal, biogas etc. and is due to the kinetic energy and the potential energy of electrons within atoms), electrical energy (associated with the electric charge and can be produced by generators from hydroelectric power stations waterfalls, geothermal stations, nuclear fissions etc.), nuclear energy from a nuclear reactor, thermal energy (due to heat produced from burning fuels, the sun, heaters etc.). In Electrical Engineering in Kenya, it is a remarkable fact about our physical universe that whenever one form of energy is lost by a body/ system, this energy never disappears but is merely translated into other forms of energy e.g. vehicles burn fuel to produce both thermal (heat) and mechanical energy.Engineering in Kenya has more information.

Mechanical Energy in Electrical Engineering in Kenya

It is the energy of motion – whether that energy is in action or stored. It exists in two forms;

Kinetic energy in Electrical Engineering in Kenya – this is energy possessed by a body by virtue of its motion and it represents the capacity of the body to do work by virtue of its speed. For Electrical Engineering in Kenya, if a force F acts on an object of mass m such that the mass accelerates uniformly from initial velocity v1 to a final velocity v2 over a distance s; then, work done over the distance s is

               W = FS. But F = ma, and S = ut + ½at2. From the relation v = u + at, then;

                t = (v-u)/a so that the work done is W = ma.s = ½m (v2 – u2) = ∆ke which is the work-energy relation theorem. In Electrical Engineering in Kenya, if a body starts from rest, then the work done on the object = kinetic energy gained by the object.

Potential Energy in Electrical Engineering in Kenya

 

Electrical Engineering in Kenya Energy in Electrical Engineering in KenyaIt is the energy possessed by a body by virtue of its configuration (position) in a force field e.g. gravitational field; magnetic field etc. if an object of mass m is lifted to a height h from the ground, then;

Work done on the mass W = F.h = mgh i.e. work done on the object = gain in the potential energy by the object. Whether a body falls vertically or slides down an inclined plane, the work done on it by gravity depends only on its mass and on the difference in height between the initial and final positions. Potential energy in Electrical Engineering in Kenya of an object depends on its location and not by the route through which it arrived at that position. It follows that if a body is transported around a closed path, the change in potential energy vanishes i.e. potential energy in Electrical Engineering in Kenya is independent of the previous history because the gravitational force is conservative. A force is said to be conservative if the work done by the force from a point A to B depends only on the position vectors rA and rB. in particular, a conservative force must not depend on time, or on the velocity or acceleration of the body.

E.g. a 100kg crate of milk is pushed up a frictionless 30o inclined plane to a 1.5m high platform. How much work is done in the process?

Solution: the x-component of mg is –mgsin30o. This force in Electrical Engineering in Kenya must be balanced by the applied force F to prevent the crate from slipping down the plane. The work done by force F is;

                 W = Fdcosᶿ

Since F acts in the direction of motion, ᶿ=0 and cosᶿ = 1. The distance over which the force acts is the name of the incline namely

                 d = 1.5/ sin30, hence W = (mgsin30)d = 1470J.

Conclusion on Energy in Electrical Engineering in Kenya

Energy in Electrical Engineering in Kenya can be converted form one form to another, but can never be destroyed. The rate of this conversion is known as power in Electrical Engineering in Kenya. Mathematically, power = ∆W/ ∆t. the unit of power is watt (W), which is the rate of work (transfer of energy) of one joule per second. Power is also measured in horsepower (hp), where 1hp = 746W in Electrical Engineering in Kenya.