Talha's Physics Academy
Frame of Reference and Types of Frames of Reference
Video Lecture: Frame of Reference
Watch the complete video lecture explaining the concept of frame of reference and its types:
Frame of Reference
In three dimensional space, a frame of reference consists of three mutually perpendicular lines called 'axes of frame of reference' meeting at a single point or origin. The coordinates of the origin are $O(0, 0, 0)$ and that of any other point 'P' in space are $P(x, y, z)$. The line joining the points $O$ and $P$ is called the position vector of the point $P$ with respect to $O$.
1. Inertial Frame of Reference
A frame of reference that remains at rest or moves with constant velocity with respect to other frames of reference is called an inertial frame of reference. An inertial frame of reference is actually an unaccelerated frame of reference. Newton's laws of motion are valid in all inertial frames of reference. In this frame of reference, a body is not acted upon by external forces (or the net external force is zero).
All inertial frames of reference are equivalent for the measurement of physical phenomena.
Examples:
- Our earth (approximated as an inertial frame for many common laboratory measurements)
- A space shuttle moving with constant velocity relative to the earth
- A rocket moving with constant velocity relative to the earth
2. Non-Inertial Frame of Reference
A frame of reference is said to be a non-inertial frame of reference when a body, not acted upon by an external force, is observed to be accelerated. In non-inertial frames of reference, Newton's laws of motion are not valid without introducing fictitious or pseudo forces.
Example: A freely falling elevator may be taken as a non-inertial frame.
No comments:
Post a Comment