Back to Projects
JOIN WHATSAPP GROUP
Free PSC MCQ 4 Lakhs+
Please Write a Review
Current Affairs 2018 to 2022
PYQ 1200 Q/A Part - 1
PYQ 1200 Q/A Part - 2
PYQ 1200 Q/A Part - 3
PYQ 1200 Q/A Part - 4
PYQ 1200 Q/A Part - 5
Kerala PSC General Science Book Study Materials Page 9
Book's First Page Skin friction is a component of drag, the The friction that exists between two force resisting the motion of a solid body surfaces those are not moving relative to through a fluid. each other. Internal friction is the force resisting motion between the elements making up a Kinetic friction solid material while it undergoes deformation. Once the Force of Static Friction is overcome, the Force of Kinetic Friction is Static friction what slows down a moving object! The coefficient of kinetic friction is The Force of Static Friction keeps a typically denoted as μk, and is usually less stationary object at rest! than the coefficient of static friction for The coefficient of kinetic friction is the same materials. typically denoted as μs The friction that exists between two surfaces those are moving relative to each other. WORK, ENERGY AND POWER Work (W) (b) body is displaced perpendicular to the direction of force, i.e., θ = 90° When a force acts on an object and the object actually moves in the direction of Work done by a force is positive if angle force, then the work is said to be done by between F and S is acute angle. the force. Work done by the force is equal to the Work done by a force is negative if angle product of the force and the displacement between F and S is obtuse angle. of the object in the direction of force. The SI unit of work is the newton-metre Work done by a constant force depends only (N m) or joule (J) and CGS unit is erg. on the initial and final Positions and not on the Its dimensional formula is [ML2T-2]. actual path followed between initial and final positions. If under a constant force F the object displaced through a distance S, then work done by the Energy (E) Force Energy of a body is its capacity of doing (W) FScos work. It is a scalar quantity. F Its SI unit is newton-metre (N m) or joule and CGS unit is erg. Its dimensional formula is [ML3T-3]. There are several types of energies, such S as mechanical energy (kinetic energy and potential energy), chemical energy, light Where W = Work, F = Force, S = energy, heat energy, sound energy, nuclear Displacement, θ = angle between force and energy, electric energy etc. displacement. Relativity - When calculating kinetic energy Work done by a force is zero, if (work to accelerate a mass from zero speed to some finite speed) relativistically - using (a) body is not displaced actually, i.e., S = 0 8