Motion is simply the change in position of an object with respect to time. Position of an object refers to the specific coordinates of the the object.
Motion could be as simple as the response of a leaf to wind or as complex as the travel of an airplane.
Motion of an object could be in five forms:
- Linear Motion
- Translational Motion
- Vibrational or Oscillatory Motion
- Random Motion
- Rotational Motion
Let’s take them one after another.
Linear motion involves the change in position of an object along a straight, definite path. It’s as simple as the motion of a car along a straight road.
An object is said to undergo translational motion when it moves from one place to another. There’s a total change in both the horizontal axis and the vertical axis as regards the coordinates or position of the object. In simple terms, the whole body changes position. For example, if I move from where I am now, to say, 5m ahead, that’s translational.
Talking about vibrational motion or oscillatory motion, an object undergoes this when moves to and fro, back and forth, with respect to a specific axis. In other words, the object in question changes position forward, comes back to the original position and then goes backward. That forms a complete cycle of oscillation. In vibratory motion, cycles occur repeatedly. A good example of vibrational motion is motion of a beating talking drum.
In random motion, an object changes position with no specific direction in mind. This is different from Oscillatory Motion in which the object moves back and forth. Here, no specific direction is quoted. An example is the movement of a flying insect, with no specific direction.
Rotational motion is a relatively different form of motion on its own. It involves the movement of an object along a circular path with regard to an INTERNAL FIXED POINT. Here, the radius of the circular path is constant. For example, the movement of the tyres of a car with respect to the centre of the tyre, the movement of the seconds hand of a clock with respect to the centre of the clock and the movement of the blades of a fan with respect to the centre of the fan are all examples of rotational motion. Examining all the example, we’ll discover that the fixed points or centres of motion are internal.
An object undergoes circular motion when it moves by the support of an external force along a circular path, with respect to an external fixed point. A stone tied to a string, when it’s whirled along a circle undergoes circular motion.
Meanwhile, a force tends to keep it moving round the circle at constant speed and prevents the motion from stopping. This force is called the Centripetal Force.
Sometimes, an object can undergo two types of motion at the same time. For instance, when a screw is being driven into a screw hole, it’s being rotated (rotational motion) and it also moves along a straight path as it enters into the screw hole (linear motion.)
In summary, motion of objects is a phenomenon that takes place in our day-to-day activities.
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