Basic Electrical Installation Work

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Therefore, speed is concerned with distance travelled and time taken. For example, the speed aircraft might 200miles/h, but its velocity would 200miles/h in, say, west- erly direction. travel in motor vehicle know that increase speed would, excluding acci- dents, allow arrive our destination more quickly. Suppose were travel a distance 30miles our speed would average 30miles/h: Speed Distance (m) Time (s) Velocity Definition Velocity everyday conversation we often use the word velocity mean the same speed, and indeed the units are the same. However, for scientific pur- poses this not acceptable since velocity also concerned with direction. Originally they were used for simple purposes, raise water and move objects which man alone could not lift, but today their principles are fundamental importance to our scientific understanding mechanics. Velocity Distance (m) Time (s) Acceleration When aircraft takes off, starts from rest and increases its velocity until it can fly. Let now consider some fun- damental mechanical principles and calculations. For scientific purposes the weight body not constant, because gravi- tational force varies from the equator the poles; space body would be ‘weightless’ but here earth under the influence gravity 1kg mass would have weight approximately 9. Weight Weight measure the force which body exerts anything which supports it. Mass Mass measure the amount material substance, such metal, plastic, wood, brick tissue, which collectively known body. The machines described him were the wedge, the screw, the wheel and axle, the pulley and the lever. The feeling speed something with which are all familiar. This change velocity called its acceleration. Definition By definition, acceleration the rate of change velocity with time. The mass body remains constant and can easily found comparing it on set balance scales with set standard masses. In everyday conversation often use the word velocity mean the same as speed, and indeed the units are the same. Definition Speed concerned with distance trav- elled and time taken. Velocity speed given direction.81N (see also the definition ‘force’).Basic electrotechnical units and theory 85 Most modern machines can traced back the five basic machines described the Greek inventor Hero Alexandria who lived about the time Christ. Definition Mass measure the amount of material substance, such metal, plastic, wood, brick tissue, which is collectively known body. Normally exerts this force because being attracted towards the earth the force gravity. The unit mass is the kilogram (kg). Speed Definition Weight measure the force which a body exerts anything which sup- ports it. . The unit mass is the kilogram (kg). definition, acceleration the rate change velocity with time. The mass body remains constant and can easily found comparing it on set balance scales with set of standard masses. Speed scalar quantity, while velocity vector quantity. Normally exerts this force because being attracted towards the earth the force gravity. However, for sci- entific purposes this not acceptable since velocity also concerned with direction