Concept explainers
What Is Static Equilibrium?
Problems 1–3 are grouped.
1. C A ball is attached to a strong, lightweight rod (Fig. P14.1). The rod is supported by a horizontal pin near the top. The ball is at rest. Is the ball in static equilibrium? If not, why not? If so, which type of equilibrium is it—stable, unstable, or neutral? Hint: What would happen if you displaced the ball slightly?
FIGURE P14.1
Whether the ball is in static equilibrium and if so the type of equilibrium in which the ball is present.
Answer to Problem 1PQ
The ball is in static equilibrium and it is stable equilibrium.
Explanation of Solution
Equilibrium is a special case of motion in which an object’s translational momentum and angular momentum are both constant. Static equilibrium is a special case in which the object’s translational momentum and angular momentum are zero. This also implies that for an object to be in static equilibrium, the total force and the total torque acting on the object must be zero. There are three types of static equilibrium namely stable static equilibrium, unstable static equilibrium and neutral static equilibrium. If an object returns to its equilibrium position after being released, it will be in stable equilibrium. If an object moves farther away from the equilibrium position after being released, it will be in unstable equilibrium. If an object is moved and released from a new position and does not move toward or away from its equilibrium position, then the object is in neutral equilibrium.
It is given that the ball in the figure is at rest so that it has no acceleration. This implies the net force and the torque acting on the ball are zero and the ball must be in static equilibrium. If the ball is displaced slightly, it will return to or pass through the equilibrium position. According to the definition, it is stable equilibrium.
Conclusion:
Thus, the ball is in stable static equilibrium since the net force and the torque acting on it is zero and it returns to its equilibrium position when it is displaced slightly.
Want to see more full solutions like this?
Chapter 14 Solutions
Physics for Scientists and Engineers: Foundations and Connections
- SECTION B Answer ONLY TWO questions in Section B [Expect to use one single-sided A4 page for each Section-B sub question.] Question B1 Consider the line element where w is a constant. ds²=-dt²+e2wt dx², a) Determine the components of the metric and of the inverse metric. [2 marks] b) Determine the Christoffel symbols. [See the Appendix of this document.] [10 marks] c) Write down the geodesic equations. [5 marks] d) Show that e2wt it is a constant of geodesic motion. [4 marks] e) Solve the geodesic equations for null geodesics. [4 marks]arrow_forwardPage 2 SECTION A Answer ALL questions in Section A [Expect to use one single-sided A4 page for each Section-A sub question.] Question A1 SPA6308 (2024) Consider Minkowski spacetime in Cartesian coordinates th = (t, x, y, z), such that ds² = dt² + dx² + dy² + dz². (a) Consider the vector with components V" = (1,-1,0,0). Determine V and V. V. (b) Consider now the coordinate system x' (u, v, y, z) such that u =t-x, v=t+x. [2 marks] Write down the line element, the metric, the Christoffel symbols and the Riemann curvature tensor in the new coordinates. [See the Appendix of this document.] [5 marks] (c) Determine V", that is, write the object in question A1.a in the coordinate system x'. Verify explicitly that V. V is invariant under the coordinate transformation. Question A2 [5 marks] Suppose that A, is a covector field, and consider the object Fv=AAμ. (a) Show explicitly that F is a tensor, that is, show that it transforms appropriately under a coordinate transformation. [5 marks] (b)…arrow_forwardHow does boiling point of water decreases as the altitude increases?arrow_forward
- How would partial obstruction of an air intake port of an air-entrainment mask effect FiO2 and flow?arrow_forward14 Z In figure, a closed surface with q=b= 0.4m/ C = 0.6m if the left edge of the closed surface at position X=a, if E is non-uniform and is given by € = (3 + 2x²) ŷ N/C, calculate the (3+2x²) net electric flux leaving the closed surface.arrow_forwardNo chatgpt pls will upvotearrow_forward
- suggest a reason ultrasound cleaning is better than cleaning by hand?arrow_forwardCheckpoint 4 The figure shows four orientations of an electric di- pole in an external electric field. Rank the orienta- tions according to (a) the magnitude of the torque on the dipole and (b) the potential energy of the di- pole, greatest first. (1) (2) E (4)arrow_forwardWhat is integrated science. What is fractional distillation What is simple distillationarrow_forward
- Physics for Scientists and Engineers: Foundations...PhysicsISBN:9781133939146Author:Katz, Debora M.Publisher:Cengage LearningPhysics for Scientists and Engineers with Modern ...PhysicsISBN:9781337553292Author:Raymond A. Serway, John W. JewettPublisher:Cengage LearningPhysics for Scientists and EngineersPhysicsISBN:9781337553278Author:Raymond A. Serway, John W. JewettPublisher:Cengage Learning
- College PhysicsPhysicsISBN:9781305952300Author:Raymond A. Serway, Chris VuillePublisher:Cengage LearningUniversity Physics Volume 1PhysicsISBN:9781938168277Author:William Moebs, Samuel J. Ling, Jeff SannyPublisher:OpenStax - Rice UniversityPrinciples of Physics: A Calculus-Based TextPhysicsISBN:9781133104261Author:Raymond A. Serway, John W. JewettPublisher:Cengage Learning