1) What effect has the position of centre of mass on the stability of an object? a) The object will overturn. b) The object will move faster. c) An object is stable if its centre of mass is low and become unstable if its centre of mass is raised. d) The object will fly high if its center of mass is raised and fly low if its center of mass is lowered. 2) Which one of the following is an application of stability? a) Trees grow tall and become widely spread on the branches. b) Bunsen burner is made with heavy and wider base to prevent fire accidents. c) Some buses are made with double decks.  d) Shorter people do not fall when they stumble against an obstacle. 3) The correct order of equilibria starting from A through B to C shown in the insert figure is..... a) Neutral, stable and unstable equilibria.  b) Unstable, neutral and stable equilibria.  c) Stable, unstable and neutral equilibria.  d) Unstable, stable and unstable equilibria. 4) Why is the bus in diagram A more stable than bus in diagram B in the insert figure? a) Because bus in diagram A has lower center of mass than that in diagram B. b) Because bus in diagram A is more neat than that in diagram B. c) Because the bus in diagram A does not have a luggage carrier over the roof. d) Because the bus in diagram A has language compartments near the bottom while bus in diagram B has no luggage compartments. 5) The cone in the insert figure returns to its original position because..... a) Because cone has larger mass at its base. b) the line of action of its weight lying along the base causes cone to turn in anticlockwise direction back to original position. c) Because cone has smaller mass at its top d) Because for is not large enough to cause cone to overturn. 6) The reason why the box overturns is because.. a) Its weight is more than mass.  b) gravity pulls on the object with greater force. c) centre of mass of a box was lowered.   d) the line of action of its weight lying outside the base causes it to turn in clockwise direction. 7) Which one of the following is a set of factors of equilibrium? a) Position of centre of mass and size of the base. b) Height and length of a body. c) Height of fall from the ground and weight of the body. d) Speed of fall and potential energy. 8) A cylindrical object comes to rest in its new position as in the original position. What type of equilibrium has it attained? a) Stable equilibrium.  b) Centre of mass c) Neutral equilibrium. d) Unstable equilibrium. 9) Equilibrium is said to be..... a) the rotational motion undertaken by a body. b) the body's state of uniformly accelerated motion. c) the action of unbalanced forces on a body d) the body's state of rest. 10) One difference between stable equilibrium and unstable equilibrium is.... a) that in stable equilibrium the body does not come back to its original position while in unstable equilibrium the body comes to rest in new position as in original position after rolling. b) that the body under stable equilibrium comes back to its original position while the body under unstable equilibrium does not come back to its original position after a tilting force is removed. c) that in stable equilibrium the net force acting on a body is zero while in unstable equilibrium there is no net force acting. d) that in stable equilibrium the center of mass slightly shifts lower while in unstable equilibrium the centre of mass shifts higher if body is disturbed from equilibrium.

Mass and Weight - Describe qualitatively the effect of the position of center of mass on the stability of an object.

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