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MECHANICS

  1. Galilean Equations of Motion under Constant Acceleration
                        (No s)
                   (No v)
                  (No t)

    where   a = constant acceleration
                u = initial velocity
                v = final velocity
                s = displacement
    and       t = time taken.

    Note: For a projectile at maximum height the speed is zero.

  2. where p is momentum, m is mass and v is velocity.
  3. Conservation of Momentum

    where a pair of masses  and  have velocities  and  respectively.
    After they interact they have velocities  and  respectively.
  4.            or        
    where F is force, p is momentum and t is time
    or         F is average force, m is mass, v is final velocity and u is initial velocity.
  5. Newton’s Second Law.

    where F is force, m is mass and a is acceleration.

  6. where W is the weight of an object of mass m and g is the acceleration due to gravity.
  7.                   and                  
    where x is the horizontal component and y is the vertical component of a vector v which is at angle of  to the horizontal.

  1. where P is pressure, F is force and A is area.

  1. where  is the density of a body with mass m and volume V.

  2. where P is the pressure in a fluid,  is the density of the fluid, g is the acceleration due to gravity and h is the depth at which the pressure is being taken.
  3. Boyle’s Law

    where P is the pressure of an ideal gas and V is its volume.

  4. where F is the gravitational force between a mass  and a mass  separated by a distance of d metres and where G is the universal gravitational constant.

  5. where g is the acceleration due to gravity at a distance d from a planet of mass M.
    G is the universal gravitational constant.

  6. where M is the moment of a force F applied at a distance d from a given point.

  7. where T is the torque (moment) of a couple, i.e. a pair of force each of magnitude F, having opposing directions and separated by a distance d.

  8. where W is the work done when a force F moves a body a distance s in the direction of the force.

  9. where  is the kinetic energy of a body of mass m and velocity v.

  10. where  is the potential energy required to move a mass m a vertical distance h and g is the acceleration due to gravity.

  11. where P is the average power when W is the work done in a time t.

  12. where  is the angle in radians corresponding to an arc length l in a circle of radius length r.

  13. where  is the average angular speed when a body in circular motion traces an angle of  radians in t seconds.

  14. where v is the tangential velocity of an object moving in a circle of radius length r with a constant angular speed .
  15.            or        
    where a is the centripetal acceleration of a body moving in a circle of radius length r with a constant angular velocity  and a tangential velocity v.
  16.        or        
    where F is the centripetal force required to keep a body of mass m moving in a circle of radius r. The body moves with a constant angular velocity  and a tangential velocity v.

  17. where v is the speed of a satellite in a circular orbit of radius R around a planet of mass M. G is the universal constant of gravitation.

  18. where T is the period of a satellite moving at a constant velocity v in a circular orbit of radius R.
  19. Kepler’s Third Law

    where T is the period of a a circular orbit of radius R around a planet of mass MG is the universal constant of gravitation.

  20. where R is the radius of a circular orbit of period T around a planet of mass MG is the universal constant of gravitation.

    Note: for a geostationary or parking orbit T = one day = 86, 400 seconds. The height, h, of such an orbit is given by , where r is the radius of the planet..
  21. Hooke’s Law

    where F is the force required to give a spring a displacement s and k is a constant of proportionality. (Note: the spring must not be extended by beyond its elastic limit.)

  22. where a is the acceleration of a body moving in simple harmonic motion when it has a displacement s from its equilibrium position. The constant of proportionality is given by .

  23. where T is the period of a body moving in simple harmonic motion with a constant of proportionality .

  24. where T is the period of a simple pendulum of length l and g is the acceleration due to gravity.