If action and reaction are equal and opposite, then how does motion occur?

   A fielder is catching a ball. Consider the action force to be the impact of the ball against the fielder's glove. What is the reaction force?

   The velocity of a particle moving in a uniform circular motion at any point is directed:

Name the rotational analog of force:

  Inertia is:

     When a running bus stops suddenly, the passengers tend to fall in the forward direction. This is due to:

     What is the product of force and time for which the force acts known as:

     A free body is acted upon by two unequal forces in opposite directions, but not in one line. The effect is that:

    What is the momentum of the bullet and of gun before firing the bullet of mass m and velocity v?

   If no external force acts on a moving body, then:

    A mechanic can open a nut by applying 120 N force while using a lever of 50 cm length. How long should the handle be, if he wishes to open, it by applying a force of only 40 N?

    Force in linear motion has its analogue in rotational motion ?

   A see-saw 8 m long is balanced in the middle. Two children of mass 30 kgf and 40kgf are sitting on the same side of the fulcrum at a distance of 1.5 m and 3.5m from the fulcrum respectively. Where must a lady weighing 60 kgf sit from the fulcrum, so as to balance the see-saw?

     A uniform metre scale of weight 50 gf is balanced at the 40 cm mark, when a weight of 100 gf is suspended at the 5 cm mark. Where must a weight of 80 gf be suspended to balance the metre scale ?

    A uniform metre scale balances horizontally on a knife edge placed at 55 cm mark, when a mass of 25 g is supported from one end. Draw the diagram of the arrangement. Calculate mass of the scale.

  A uniform metre scale is balanced at 20 cm mark, when a weight of 100 gf is suspended from one end. Where must the weight be suspended? Calculate the weight of the metre scale.

  A uniform metre scale is balanced at 60 cm mark, when weights of 5 gf and 40 gf are suspended at 10 cm mark and 80 cm mark respectively. Calculate the weight of the metre scale.

    Two forces each of magnitude 2N act vertically upward and downward respectively on two ends of a uniform rod of length 1m, freely pivoted at its centre. Determine the resultant moment of forces about the mid-point of the rod.

Calculate the length of the arm of couple, if a force of 13 N produces a moment of couple of 14.3 Nm.

    A couple of 15 N force acts on a rigid body, such that the arm of couple is 85cm. Calculate the moment of couple in S.I. system.

  Calculate the force which will produce a moment of force of 1575 dyne cm, when the perpendicular distance between point of application of force and turning point is 45 cm.

   A force of 50 N produces a moment of force of 10 Nm in a rigid body. Calculate the perpendicular distance between the point of application of force and the turning point is 45 cm.

   The perpendicular distance between the point of application of force and the turning point is 1.75 m, when a force of 80 N acts on a rigid body. Calculate the moment of force.

  A force of 50 dynes acts on a rigid body, such that the perpendicular distance between the fulcrum and the point of application of force is 75 cm. Calculate the moment of force.

A body is describing a uniform circular motion. Which of the following quantities is/are constant?

The centre of gravity of a cricket ball is at:

   The unit of moment of force in SI system is:

    The turning effect produced in a rigid body around a fixed point by the application of force is called:

The moment of a force 5 N about a point P is 2 N m. Calculate the distance of point of application of the force from the point P.

   Centre of gravity of a hollow cone of height h is at distance x from its vertex where the value of x is:

  The centre of gravity of a uniform ball is:

     A nut is opened by a wrench of 10 cm. If the least force required is 10 N, find the moment of force needed to turn the nut.

     What should be the value of algebraic sum of moment of all forces of a body about the point of rotation?

What is the value of resultant force acting on an equilibrium body?

How many types of equilibrium you know?

     What is needed to open a shut door?

     We take negative sign for which moment of force?

    We take positive sign for which moment of force?

    1gf = ___ dyne

     1kgf = ___ N

     What is the CGS unit of moment of force?

     What is the SI unit of moment of force?