FORCE AND PRESSURE By Nitin Oke

Which of the following are True / False 1.A push or a pull on an object is called a force. 2.At least three objects must interact for a force to come into play. 3.Forces applied on an object in the same direction the net force acting on an object, is difference of two forces. 4.If the two forces act in the opposite directions on an object, the net force acting on it is the sum of the two forces.

Which of the following are True / False 5.In general, more than one force may be acting on an object. However, the effect on the object is due to the net force acting on it. 6.The strength of a force is usually expressed by its magnitude. 7.If the force applied on the object is in the direction of its motion, the speed of the object increases.

Which of the following are True / False 8.If the force is applied in the direction opposite to the direction of motion, then it results in a decrease in the speed of the object. 9.A force will always bring a change in the state of motion of an object. 10.Force on an object may change its shape.

Which of the following are True / False 11.The force resulting due to the action of muscles is known as the human force. 12.The force exerted by a magnet is an example of a non-contact force. 13.The electrostatic force, is example of a non- contact force. 14.The gravitational force, is example of a non- contact force. 15. The only contact force is muscular force.

Which of the following are True / False 16.Gravity is NOT a property of the earth alone. 17.The force acting on a unit area of a surface is called pressure. 18.Shoulder bags are provided with thin straps to reduce pressure on shoulder. 19.The direction of atmospheric pressure in downward. 20. for constant force if area over which force is exerted increase then pressure also increases

Fill up the gap by appropriate word write ONLY word to add (1) To draw water from a well we have to ——— the rope. (2) A charged body ———— an uncharged body towards it. (3) To move a loaded trolley we have to ———— it. (4) The north pole of a magnet ———— the north pole of another magnet.

Use muscular, contact, non-contact, gravity, friction, shape, attraction to fill the gaps (a) To stretch the bow, the archer applies a force that causes a change in its ——. (b) The force applied by the archer to stretch the bow is an example of ——— force. (c) The type of force responsible for a change in the state of motion of the arrow is an example of a —— —— force. (d) While the arrow moves towards its target, the forces acting on it are due to ———— and that due to ———— of air.

Answer in short at most one sentence (1) Name the forces acting on a plastic bucket containing water held above ground level in your hand (2) When we press the bulb of a dropper with its nozzle kept in water, air in the dropper is seen to escape in the form of bubbles. Once we release the pressure on the bulb, water gets filled in the dropper. The rise of water in the dropper is due to what? (3) An inflated balloon was pressed against a wall after it has been rubbed with a piece of synthetic cloth. It was found that the balloon sticks to the wall. Why?