Sir, I was going through some questions in H.C.Verma and have a few doubts as follows:1) A disk rotates about its axis with a constant angular acceleration of 4 rad/s^2.Find the radial and tangential accelerations of a particle at a distance of 1 cm from the axis at the end of the first second after the disk starts rotating.I used the formula @=a/Rwhere:@=tangential accelerationa=angular accelerationR=radiusSusbstituting the values i got the correct answer 4 cm/s^2. However how do you find the radial acceleration?2)Three particles,each of mass 200g are kept at the corners of an equilateral triangle of side 10cm.Find the moment of Inertia of the system of an axisa)joining two of the particles andb)passing through one of the particles and perpendicular to the plane of the particles.For this question I drew the figure and tried to go about it but couldn't get it. The answers given in the book are:a)1.5*10^-3 kg/m^2b)4.0*10^-3 kg/m^23)Particles of masses 1g,2g,3g,.....,100g are kept at the maks 1cm,2cm,3cm....100cm respectively on a metre scale.Find the moment of inertia of the system of particles about a perpendicular bisector of the metre scale.The answer given is:0.43 kg/m^2

R Gopalakrishnan , 15 Years ago

Grade 11