Scalar and vector quantities for IGCSE Physics, GCE O level Physics

Transcript

foreign physical quantities all physical quantities consist of a numerical magnitude and a unit for example the volume of 150 cubic meters the volume is the physical quantity the value of 150 represents the numerical magnitude or size of the volume the cubic meters represents the unit of volume there are two types of physical quantities as scalar and vector the volume is scalar quantity because the volume has no the direction the force of 10 Newtons the force is physical quantity the value of 10 represents the numerical magnitude or size of the force the Newton is the unit of force the right direction represents forces Direction the Force's vector quantity because it has both magnitude and direction scalar and vector a scalar quantity has only magnitude or size which is a numerical value a vector quantity has both magnitude and direction for example some scalar quantities in physics include distance speed time mass energy or work or power density and temperature for example some Vector quantities in physics include displacement velocity acceleration force or weight momentum electric field strength and gravitational field strength resultant vector resultant Vector is the total or net vector Vector quantities are represented by arrows the arrowhead indicates the direction of the vector the length of the arrow represents the magnitude there are two methods that can be used to find the resultant Vector as the triangle method and the parallelogram method to add the vector a and Vector B using the triangle method we are given the vector a and Vector b as shown link the head of vector a to the tail of vector B the resultant Vector is formed by connecting the tail of the vector a to the head of the vector B to add the vector a and Vector B using the parallelogram method link the Tails of the vector a and Vector B draw a parallelogram with Vector a and Vector B asides the resultant Vector is the diagonal of the parallelogram determine the resultant of two vectors at right angles by calculation find the resultant velocity of an airplane that is flying of 80 kilometers per hour in a 60 kilometers per hour crosswind as shown in the diagram draw a parallelogram with 80 kilometers per hours and 60 kilometers per second asides which form to the rectangular the resultant velocity is the diagonal of the parallelogram we can calculate the magnitude of the resultant velocity using the Pythagorean theorem resultant velocity squared equals 80 squared plus 60 squared resultant velocity equals square root of 80 squared plus 60 squared equals 100 kilometers per hour we can calculate the direction of the resultant velocity by the tangent ratio the direction of the resultant velocity is tan power minus 1 of 80 over 60 is equal to 53 degrees to 60 kilometers per hour find the resultant velocity using the triangle method and graphically set the scale 1 centimeter to 10 kilometers per hour draw the velocity of 60 kilometers per hour to write for six centimeters measure angle at the head of the 60 kilometers per hour velocity using a protractor as 90 degrees length ahead of the 60 kilometers per hour velocity to the tail of the 80 kilometers per hour velocity draw a velocity of 80 kilometers per hour for 8 centimeters the resultant velocity is formed by connecting the tail of the 60 kilometers per hour velocity to the head of the 80 kilometers per hour measure the length of the resultant velocity so magnitude of the resultant velocity is 10 centimeters times 10 kilometers per hour equals 100 kilometers per hour measure the angle between the 60 kilometers per hour and resultant velocity so the direction of the resultant velocity is 53 degrees to 60 kilometers per hour I hope you found this video helpful if you did I would be grateful if you would subscribe to my channel share this video with your friends and leave a positive comment your support will help me to continue making videos and encourage me to create new content thank you