Basic Electrical Installation Work

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81N (see also the definition ‘force’). Speed Definition Weight measure the force which a body exerts anything which sup- ports it. Mass Mass measure the amount material substance, such metal, plastic, wood, brick tissue, which collectively known body. Speed scalar quantity, while velocity vector quantity. In everyday conversation often use the word velocity mean the same as speed, and indeed the units are the same. This change velocity called its acceleration. The feeling speed something with which are all familiar. Definition By definition, acceleration the rate of change velocity with time. The machines described him were the wedge, the screw, the wheel and axle, the pulley and the lever. Velocity Distance (m) Time (s) Acceleration When aircraft takes off, starts from rest and increases its velocity until it can fly. Definition Speed concerned with distance trav- elled and time taken. travel in motor vehicle know that increase speed would, excluding acci- dents, allow arrive our destination more quickly. 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. However, for scientific pur- poses this not acceptable since velocity also concerned with direction. 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. The unit mass is the kilogram (kg). 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. Therefore, speed is concerned with distance travelled and time taken. 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. Definition Mass measure the amount of material substance, such metal, plastic, wood, brick tissue, which is collectively known body. The mass body remains constant and can easily found comparing it on set balance scales with set standard masses. Velocity speed given direction. definition, acceleration the rate change velocity with time.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. . Normally exerts this force because being attracted towards the earth the force gravity. The mass body remains constant and can easily found comparing it on set balance scales with set of standard masses. For example, the speed aircraft might 200miles/h, but its velocity would 200miles/h in, say, west- erly direction. The unit mass is the kilogram (kg)