Question

Problem 3.13 Bad A has 2 kg mass and slides without friction on bar BC. a) Determine the force needed to keep the bead in static equilibrium and the reaction force between the bead and bar. b) If the value of F determined in Part (a) is applied, will the bead move? Explain. -) ITF is larger than the value determined in Part (a), describe what happens. Figure P3.13

Answer 1

FBD sink 30 mg cos 30 Along the normal to the inclined plane, we have the force equilibrium: N = mg cos 30 + F sin 30 Along the inclined plane we have: F cos 30 = mg sin 30 F = mg tan 30 = 2 x 9.8 x tan 30 = 11.3 N Thus, Normal force is: N = 11.3 x sin 30 + 2 x 9.8 x cos 30 = 22.63 N b) No, if the force of magnitude as found in (a) is applied, block does not move as it will remain at rest. c) If the force is larger, the bead will tend to move upwards.