IIT JEE Physics Preparation

Average speed can be defined as the  total distance traveled divided by given time interval . In other words, it can be represented as a function of total path length traveled divided by total time interval. It is a scalar quantity. Thus, it is measured using magnitude only. The average speed is independent of the direction in which object moved. $Average Speed = \frac{Total Path Length}{Total Time Interval}$ Let's say, the body is at a point P (O being a reference point in a one-dimensional frame of reference) at time 2:00 pm. In next 1 minute, it traveled 1 km. In another 3 minute, it traveled 5 km. The average speed of the body can be calculated as the following: $\frac{1000 + 5000}{60 + 180}$ = $\frac{6000}{240}$ = 25 $\frac{m}{s}$

Let's try and understand the difference between distance and displacement. Distance is a scalar quantity . It is a physical entity which is used to describe the motion of an object in terms of the path traveled by the object. Simply speaking, distance is the total length of the path traveled by an object irrespective of the direction. In a one-dimensional frame of reference, let's say the origin or reference point is represented by O. At time t, the body is at a point, P which 10 meters away from O. The object started moving and reached to the point P by traveling 50 meters at time t2 and reached to the point R at time t3 by traveling 100 meters and traveled back to Q by traveling 25 meters.  Q is 135 meters away from the point O. The total distance traveled by the object is following: 10 + 50 + 100 + 25 = 185 meters Displacement is a vector quantity . It is defined as the change of position of the object with respect to a reference point. Taking ab...

Motion is the change of position of an object from one point to other in a given period of time. Motion can be described using different entities such as some of the following: Reference point : In order to define the position of an object, one needs to understand the concept of the reference point and a set of axes.  For three dimensional coordinate system comprising of mutually perpendicular x, y and z-axis, the intersection point of these axes are called as a reference point. It is also called the origin.  For a two-dimensional coordinate system having x and y-axis as mutually perpendicular axes, the point of intersection becomes the reference point, also termed as the  origin . For a one-dimensional system, the point where the motion starts can be taken as the reference point also termed as the origin . The frame of reference : Frame of reference comprises a reference point (origin) and is used to describe the motion of the body with respect ...

Newton's first law of motion states that a body in rest or motion would tend to remain in the same until an external force is applied against it. The following is a couple of examples in relation to Newton's first law of motion: When you try stepping down from a moving bus, you tend to fall down unless you run as you step down. The reason is as you step down, your body which was in motion tend to remain in the same state while your feet stop. Thus, the upper part of body pushes forward resulting in you falling down. On the other hand, if you went on to run as you stepped down, you would have maintained the first law of motion and not fell down.