Moving in the vertical plane against gravity

Moving in the vertical plane against gravity

Section 1: Vertical Motion Basics

  • Learn that an object moving in a vertical plane moves under the influence of gravity along with any other forces acting upon it.
  • Understand that the force of gravity acts downwards and is denoted as weight, calculated as mass times gravitational acceleration (g).
  • Remember that gravitational acceleration is approximately 9.8 m/s² downwards.

Section 2: Upwards Motion

  • Recognise that when an object moves upwards, it does so against gravity, which decelerates the object.
  • Be aware that the object’s velocity will decrease until it reaches its maximum height with a final velocity of zero, before it starts descending.

Section 3: Downwards Motion

  • Understand that when an object begins to descend, gravity acts as an accelerator, thus increasing its velocity.
  • Remember, unlike horizontal motion, vertical motion is not uniform due to the constant force of gravity.

Section 4: Equations of Motion

  • Learn to apply the equations of motion that involve initial velocity, final velocity, acceleration, time and distance in a vertical plane.
  • Become familiar with vector notation to represent vertical motion where upwards direction is denoted as positive, and the downward direction is considered negative.
  • Note, for an object projected upwards, initial velocity is positive, and acceleration (due to gravity) is negative.

Section 5: Air Resistance

  • A more complex scenario involves considering air resistance along with gravity, which also opposes the motion, especially at higher speeds.
  • Understand that air resistance depends on various factors like shape, area and velocity of the object.

Section 6: Problem-Solving

  • Master using equations of motion to solve problems related to vertical motion, like calculating the maximum height, time of flight, and final velocity.
  • Practice applying laws of motion to cases of suspended objects and tension in strings where forces are balanced.
  • Regularly test your understanding of vertical motion principles and problem-solving methods through ample problem drills.