SAMPLE-PROBLEMS-IN-STATICS-OF-RIGID-BODIES (1).docx

SAMPLE PROBLEMS IN STATICS OF RIGID BODIES 1. Which of the following is NOT a condition for a rigid body to be in equilibrium? A. ∑Fx = 0 B) ∑Fy = 0 C) ∑M = 0 D) ∑F = 0 Answer: D) ∑F = 0 2. The force that keeps a body in equilibrium under the action of external forces is called:...

SAMPLE PROBLEMS IN STATICS OF RIGID BODIES 1. Which of the following is NOT a condition for a rigid body to be in equilibrium? A. ∑Fx = 0 B) ∑Fy = 0 C) ∑M = 0 D) ∑F = 0 Answer: D) ∑F = 0 2. The force that keeps a body in equilibrium under the action of external forces is called: A. Reaction force B) Equilibrant force C) Resultant force D) None of the above Answer: B) Equilibrant force 3. When a body is in equilibrium, which of the following statements is true? A. The sum of all external forces is zero. B. The sum of all internal forces is zero. C. The sum of all moments about any point is zero. D. All of the above Answer: D) All of the above 4. What is the resultant of two concurrent forces acting in opposite directions? A. Zero B. The sum of the magnitudes of the forces C. The difference of the magnitudes of the forces D\) The average of the magnitudes of the forces Answer: A) Zero 5. The moment of a force about a point is the product of the force magnitude and the: A. Direction of the force B. Distance from the point to the line of action of the force C. Angle between the force and the point D. None of the above Answer: B) Distance from the point to the line of action of the force 6. Which of the following statements regarding a couple is true? A. A couple is formed by two parallel forces with the same magnitude but opposite direction. B. A couple always has a resultant force. C. A couple cannot produce rotation. D. None of the above Answer: A) A couple is formed by two parallel forces with the same magnitude but opposite direction. 7. The principle of transmissibility states that: A. A force can be transferred along its line of action without changing its effect on a body. B. A force can be transferred to any point on a body without affecting equilibrium. C. A force can be transmitted through a rigid body. D. None of the above Answer: A) A force can be transferred along its line of action without changing its effect on a body. 8. A force of 50 N is applied at an angle of 30 degrees to the horizontal. What are the horizontal and vertical components of this force, respectively? A. 25 N, 43.3 N B) 43.3 N, 25 N C) 50 N, 0 N D) 0 N, 50 N Answer: A) 25 N, 43.3 N 9. Which of the following is a scalar quantity? A\) Force B) Velocity C) Acceleration D) Displacement Answer: D) Displacement 10. The force exerted by a body against a surface in contact with it is called: A\) Reaction force B) Resultant force C) External force D) Equilibrant force Answer: A) Reaction force 11\. Which of the following is NOT a method for resolving forces? A\) Graphical method B) Analytical method C) Trigonometric method D) Moment method Answer: D) Moment method 11. When a body is subjected to a system of parallel forces in the same plane, it will remain in equilibrium if: A. The sum of the forces is zero. B) The sum of the moments about any point is zero. B. The sum of the forces and moments is zero. D) None of the above Answer: C) The sum of the forces and moments is zero. 12. Which of the following statements regarding equilibrium is true? A. A body in equilibrium cannot be in motion. B. A body in equilibrium has all its particles at rest. C. A body in equilibrium may be in translational or rotational motion. D. None of the above Answer: C) A body in equilibrium may be in translational or rotational motion. 13. The moment of a force about a point is minimum when the force: A. Acts perpendicular to the point B. Acts parallel to the point C. Acts at an acute angle to the point D. Acts at an obtuse angle to the point Answer: A) Acts perpendicular to the point 14. Which of the following is true about the moment of a couple? A. It is the same about all points. B. It depends on the orientation of the couple. C. It is a vector quantity. D. None of the above Answer: A) It is the same about all points. 15. A force of 100 N is applied horizontally to a block on a frictionless surface. What is the normal force acting on the block? A\) 100 N B) 50 N C) 0 N D) Cannot be determined without additional information Answer: A) 100 N 16. When a body is subjected to a system of parallel forces, the equilibrant is: A. The force needed to maintain equilibrium B. The resultant of the forces C. The sum of the forces D. None of the above Answer: A) The force needed to maintain equilibrium 17. Which of the following is a condition for a body to be in translational equilibrium? A. ∑Fx = 0 B) ∑Fy = 0 C) ∑Fz = 0 D) All of the above Answer: D) All of the above 18. Two forces of 10 N and 15 N act at right angles to each other. What is the magnitude of their resultant force? A. 25 N B) 5 N C) 18 N D) 20 N Answer: D) 20 N 19. Which of the following is NOT a unit of moment? A\) Newton-meter B) Joule C) Pound-foot D) Dyne-centimeter Answer: B) Joule 20. Which of the following statements regarding the principle of moments is true? A. It states that the sum of the moments about any point is equal to zero. B. It states that the clockwise moments equal the counterclockwise moments about any point. C. It states that the moment arm is perpendicular to the force. D. None of the above Answer: B) It states that the clockwise moments equal the counterclock 21. Which of the following best defines a force? A. The speed of an object B. The resistance of an object to motion C. A push or pull acting on an object D. The energy possessed by an object Answer: C) A push or pull acting on an object 22. Which of the following units is used to measure force in the International System of Units (SI)? A. Newton (N) B) Kilogram (kg) C) Meter per second (m/s) D) Joule (J) Answer: A) Newton (N) 23. According to Newton\'s first law of motion, an object will remain at rest or in uniform motion in a straight line unless acted upon by: A\) Friction B) Inertia C) Force D) Acceleration Answer: C) Force 24. Which of the following statements best describes Newton\'s third law of motion? A. For every action, there is an equal and opposite reaction. B. An object in motion will stay in motion unless acted upon by an external force. C. The acceleration of an object is directly proportional to the net force acting on it. D. The velocity of an object remains constant if the net force acting on it is zero. Answer: A) For every action, there is an equal and opposite reaction. 25. Two objects with masses of 5 kg and 10 kg, respectively, experience the same force. According to Newton\'s second law of motion, which of the following statements is true? A. The object with a mass of 5 kg will experience a greater acceleration. B. The object with a mass of 10 kg will experience a greater acceleration. C. Both objects will experience the same acceleration. D. The acceleration of each object cannot be determined without additional information. Answer: A) The object with a mass of 5 kg will experience a greater acceleration. 26. If an object has a mass of 2 kg and experiences a force of 10 N, what is its acceleration? A. 5 m/s² B) 2 m/s² C) 20 m/s² D) 12 m/s² Answer: C) 20 m/s² 27. Which of the following statements regarding forces in equilibrium is true? A. The net force acting on an object in equilibrium is zero. B. Objects in equilibrium must be at rest. C. Equilibrium is only possible when there are no forces acting on an object. D. Equilibrium is not affected by the direction of the forces acting on an object. Answer: A) The net force acting on an object in equilibrium is zero. 28. Which of the following is an example of a contact force? A. Gravitational force B. Magnetic force C. Electrostatic force D. Normal force Answer: D) Normal force 29. If a force of 20 N is applied to an object with a mass of 5 kg, what is the object\'s acceleration? A. 4 m/s² B) 20 m/s² C) 100 m/s² D) Cannot be determined without additional information Answer: A) 4 m/s² 30. Which of the following statements best describes the relationship between force and acceleration? A) Force is directly proportional to acceleration. B. Force is inversely proportional to acceleration. C. Force and acceleration are unrelated. D. Force causes displacement, not acceleration. Answer: A) Force is directly proportional to acceleration. 31. What is a vector quantity? A. A quantity with only magnitude B. A quantity with both magnitude and direction C. A scalar quantity D. A quantity with only direction Answer: B 32. Which of the following is a scalar quantity? A. Velocity B) Force C) Displacement D) Mass Answer: D 33. Which operation is used to add vectors graphically? A\) Subtraction B) Multiplication C) Division D) Head-to-tail addition Answer: D 34. What is the result of adding two collinear vectors? A. The sum is always zero B. The sum is the sum of their magnitudes C. The sum is the difference of their magnitudes D. The sum is the product of their magnitudes Answer: B 35. What is the magnitude of the zero vector? A. Zero B) One C) Infinity D) Undefined Answer: A 36. Which of the following is a unit vector? A. (2, 3) B) (1, 1) C) (0, 0) D) (0, 1) Answer: D 37. What is the dot product of two perpendicular vectors? A. 0 B) 1 C) -1 D) Infinity Answer: A 38. What is the result of subtracting a vector from itself? A. The zero vector B. The original vector C. A scalar quantity D. The negative of the original vector Answer: A 39. Which of the following represents a vector in two-dimensional space? A. (2, 3, 4) B) (2, 3) C) (2) D) (2, 3, 4, 5) Answer: B 40. Which operation is used to find the angle between two vectors? A. Addition B) Subtraction C) Dot product D) Cross product Answer: C 41. What is the cross product of two parallel vectors? A. 0 B) 1 C) -1 D) Infinity Answer: A 42. Which of the following is true about the magnitude of a vector? A. It is always positive B. It can be negative C. It can be zero D. It is always greater than 1 Answer: A 43. What is the result of multiplying a vector by a scalar? A. Another vector B. A scalar quantity C. The zero vector D. The magnitude of the vector Answer: A 44. Which operation is used to find the component of a vector along a given direction? A. Addition B) Subtraction C) Dot product D) Projection Answer: D 45. What is the magnitude of the cross product of two vectors? A. It depends on the vectors B. The product of their magnitudes C. The sum of their magnitudes D. The difference of their magnitudes Answer: A 46. What is the angle between two parallel vectors? A. 0° B) 90° C) 180° D) 270° Answer: A 47. What is the magnitude of the projection of a vector onto itself? A. It depends on the vector B. The magnitude of the vector C. Zero D. Infinity Answer: B 48. Which of the following represents the direction of a vector? A. Its magnitude B. Its components C. Its angle with respect to a reference axis D. Its projection Answer: C 49. What is the result of adding a vector and its negative? A. The zero vector B. The original vector C. A scalar quantity D. The negative of the original vector Answer: A 50. Which of the following represents the cross product of two vectors? A. A scalar quantity B. Another vector C. The zero vector D. The magnitude of the vectors Answer: B