Tiêu đề 7. Work,power & energy Allen.pdf ✅

 Digital Pvt. Ltd. [1] Work Whenever a force acts on a body, displaces its point of application of force in any direction except perpendicular to it, work is said to be done by the force. If a constant force is applied on a body and displaces it through displacement then work done by on the body is given by scalar product of and . Mathematically, Ǥ Where is angle between and . Units and Dimensions Unit SI Unit of work : Joule (J) Joule : One joule of work is said to be done when a force of one newton displaces a body by one meter in the direction of force. 1 joule = 1 newton × 1 meter = 1 kg-m2/s2 Erg : One erg of work is said to be done when a force of one dyne displaces a body by one centimeter in the direction of force. 1 erg = 1 dyne × 1 cm = 1 g-cm2/s2 Other Units : (a) 1 joule = 107 ergs (b) 1 erg = 10–7 joules (c) 1 eV = 1.6 × 10–19 joules (d) 1 joule = 6.25 × 1018 eV (e) 1 MeV = 1.6 × 10–13 J (f) 1 J = 6.25 × 1012 MeV (g) 1 kilowatt-hour (kWh) = 3.6 × 106 joules Dimensions [Work] = [Force] [Displacement]= [MLT–2][L] = [ML2T–2] Introduction of Work Part -01