A door lock is opened by turning the lever (handle) of length 0.2 m. If the moment of force produced is 1 Nm, then the minimum force required is: (a) 5 N (b) 10 N (c) 20 N (d) 0.2 N

Fill in the blanks: (a) A stone tied to a string is rotated in a horizontal plane. The tension in the string provides the __________ force necessary for circular motion. (b) The work done by this force at any instant is __________.

A non-uniform beam of weight 120 N pivoted at one end is shown in the diagram below. Calculate the force F required to keep the beam in equilibrium.

(a) Define Centre of Gravity. (b) A hollow ice cream cone has height 6 cm. (i) Where is the position of its centre of gravity from the broad base? (ii) Will its position change when it is filled completely with honey? Write Yes or No.

Clockwise moment produced by a force about a fulcrum is considered to be: (a) Positive (b) Negative (c) Zero (d) None of these

Which among the following is a vector quantity? (a) work (b) power (c) energy (d) moment of couple

A body is acted upon by two equal and opposite forces, that are NOT along the same straight line. The body will : (a) remain stationary (b) have only rotational motion (c) have only rectilinear motion (d) have both rectilinear and rotational motion

For a body to be in dynamic equilibrium: (a) its momentum must be zero (b) its acceleration must be zero (c) its kinetic energy must be zero (d) its velocity must be zero

A non-uniform kite is hanging freely from the branch of a tree as shown. Study the figure and answer the following: (a) Fill in the blank. ............... [P, Q, R or S] is the most probable position of its centre of gravity. (b) Support your answer to (a) with a reason.

A metre scale of weight 50 gf can be balanced at 40 cm mark without any weight suspended on it. (a) If this ruler is cut at its centre then state which part [0 to 50 cm or 50 to 100 cm] of the ruler will weigh more than 25 gf. (b) What minimum weight placed on this metre ruler can balance this ruler when it is pivoted at its centre?

The diagram shows wheel O pivoted at point A. Three equal forces F1, F2 and F3 act at point B on the wheel. (a) Which force will produce maximum moment about A? (b) Give a reason for your answer in (a).

(a) What is the position of centre of gravity of a triangular lamina? (b) When this triangular lamina is suspended freely from any one vertex, what is the moment of force produced by its own weight in its rest position?