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Mechanics is the study of the interactions between physical bodies and their consequent motion.

In this topic, we will:

  • Define the quantities used to describe motion (displacement, velocity, acceleration).
  • Derive a set of equations that give the relationship between the displacement, velocity, acceleration and time when the acceleration is constant.
  • Solve problems involving constant acceleration in 1 and 2-dimensions.
  • Understand the effects of forces.
  • Relate unbalanced forces to motion.
  • Consider energy and the capabilities that this gives to bodies.
  • Define power and efficiency.
  • Learn about types of collision in terms of conservation of momentum.

  • Force vs displacement graphs

    A force vs displacement graph is a useful tool for measuring the work done when the force is not constant.

  • Work done

    When asked the question, "is work done", you should always think of the definition of work and use it in your answer. Work is done if a force moves in the direction of the line of action of the force.

  • Inertia, momentum and impulse

    Heavy bodies require a large force to get then moving and a large force to make them stop. We say the body has a larg inertia.

  • Work and energy

    To predict the outcome of the collision between two ball we need more than just the conservation of momentum, we neeed to consider energy as well.

  • Potential energy

    It might be better to call potential energy positional energy since it is the energy a body has due to its position.

  • Projectile motion

     Not very nice to shoot monkeys but it makes a good point about the vertical component of projectile motion so it´s for a good cause. Best to think of projectile motion as two problems in one, constant velocity horizontally and constant acceleration ver