Draw the diagram. Next resolve the weight of the block into normal, and down the plane components.
Up the plane force is 3g
Friciton is mgCosTheta*mu
Now sum forces: Assume friction is down the plane.
Net force= totalmass*a
solve for a. If a is zero, then you chose the wrong direction for friction, and you know answer a).
A doubly tethered model airplane of mass 1.0 kg is attached to a vertical rod by two very light strings that are 2.0 each in length. the airplane and the the strings rotate in a horizontal circleabout the rod with both the strings remaining taut.The attachment points of the strings are also seperated by 2.0 m If the tension in the upper string is 39.2 N. Calculate
a)the tension in the lower string.Is it likely to be less or more than the tension in the upper string?
b)the steady speed of the ball as it undergoes circular motion.