Answer to Question #39684 in Mechanics | Relativity for rakshu

Question

1) A spaceman in training is rotated in a seat at the end of a horizontal arm of lenght 5m. if he can withstand up to acceleration 9g, what is max number of revolutions/second permissible? g=10m/s^2
2)a small coin of mass 80g is placed on the horizontal surface of a rotating disc. the disc starts from rest and is given a constant angular acceleration of 2rad/s^2. the coefficient of static friction between coin and disc is 0.75 and coefficient of kinetic friction is 0.5. the coin is placed at a distance of 1m from the centre of disc. what is the magnitude of the resultant force on coin exerted by the disc just before it starts slipping on the disc?
3)a small body of mass 0.1kg swings a vertical circle at the end of a cord of lenght 1m. if its speed is 2m/s when the cord makes an angle 30 degree with the vertical. find i)radial and tangential components of acceleration at this instant ii)the magnitude and direction of the resultant acceleration iii) the tension in the cord