Force Systems Push, pull, and play with forces!From resultants to components, this section tests how well you balance, resolve, and conquer every mechanical challenge. 1 / 20 The condition for two forces to be in equilibrium is that they must be — Equal, opposite, and collinear Equal and parallel Unequal and concurrent Parallel and perpendicular Equal, opposite, and collinear forces cancel each other perfectly. 2 / 20 If the resultant of all forces acting on a body is zero, the body is said to be — In equilibrium In motion Rotating Vibrating Zero resultant means balanced forces — no acceleration, hence equilibrium. 3 / 20 The vector sum of all forces acting on a body is — Power Resultant force Work Moment The resultant is the vector addition of all applied forces. 4 / 20 The direction of the resultant force can be found using — Newton’s laws Parallelogram law of forces Hooke’s law Bernoulli’s equation The parallelogram law gives both magnitude and direction of the resultant. 5 / 20 The point about which the algebraic sum of moments of all forces is zero is called — Center of gravity Moment center or point of rotation Axis of motion Plane of force That point is the rotational reference where moments balance. 6 / 20 When two forces are equal, opposite, and collinear, their resultant is — Zero Twice one force Infinity Equal to one force Infinity Equal to one force Equal and opposite forces cancel out completely. 7 / 20 A non-concurrent, non-parallel force system is known as — General force system Coplanar system Concurrent system Parallel system General system means forces act in different directions, not meeting at one point. 8 / 20 The line of action of a force passes through — Center of gravity The direction in which the force acts Moment center Axis of rotation The line of action represents the straight line along which the force acts. 9 / 20 If a body is acted upon by two equal and opposite forces but not in the same line, the body — Remains in equilibrium Rotates about a point Moves in a straight line Vibrates Equal and opposite non-collinear forces form a couple, causing rotation. 10 / 20 The polygon law of forces is used to find — Torque Resultant of several concurrent forces Mass Acceleration The polygon law helps determine the resultant of multiple concurrent forces. 11 / 20 Lami’s theorem is applicable for — Three concurrent forces in equilibrium Any number of forces Parallel forces Rotational systems Lami’s theorem applies when three forces keep a body in equilibrium. 12 / 20 A system of coplanar parallel forces means — Forces act in one plane and are parallel Forces act at one point Forces act in different planes None of these “Coplanar parallel” means all forces lie in the same plane and are parallel. 13 / 20 If several concurrent forces act on a body, their resultant will pass through — The common point of concurrency Center of gravity Base Axis of rotation Resultant of concurrent forces passes through their intersection point. 14 / 20 The resultant of two equal and opposite forces acting along the same line is — Zero Twice one force Half one force Infinity Equal and opposite forces cancel each other out. 15 / 20 The moment of a couple is — Half the force × distance Equal to one of the forces Force × perpendicular distance Zero Moment of couple = Force × arm distance. 16 / 20 A couple produces — Linear motion Rotation only Vibration Translation A couple creates pure rotational motion without translation. 17 / 20 The parallelogram law of forces is applicable when — Forces are parallel Forces act at 90° Forces act at a point Forces are opposite It applies to forces acting at a single point and at an angle to each other. 18 / 20 The resultant of two perpendicular forces of equal magnitude F is — F F√2 2F F/√2 By Pythagoras theorem, resultant R = √(F² + F²) = F√2. 19 / 20 If the resultant of two equal forces is equal to one of the forces, the angle between them is — 0° 45° 120° 180° When R = F, using the law of parallelogram gives cosθ = -½ → θ = 120°. 20 / 20 Two or more forces acting on a body are called a system of forces when they — Meet at a point Act on a single body Are equal in magnitude Are parallel A system of forces exists when multiple forces act simultaneously on one body. Your score isThe average score is 56% 0% Restart quiz
