Per NCERT, in motion problems we treat objects as POINT OBJECTS. When is this approximation valid?
AWhen the size of the object is much SMALLER than the distance it moves in a reasonable duration of time
BAlways — regardless of size
COnly for stationary objects
DOnly for fast objects
Answer & Solution
Correct answer: A. When the size of the object is much SMALLER than the distance it moves in a reasonable duration of time
Per NCERT §2.1, point-object approximation is valid when size ≪ distance covered.
Related questions
Per NCERT, what is INSTANTANEOUS SPEED equal to (in MAGNITUDE) — at a given instant?Per NCERT, in KINEMATICS, what aspect of motion is studied?Per NCERT, what is RECTILINEAR motion?Per NCERT, why is AVERAGE SPEED over a finite interval always GREATER than or EQUAL to thePer NCERT, an object has instantaneous velocities of +24 m/s and −24 m/s at two different Per NCERT, what is INSTANTANEOUS SPEED of an object?Per NCERT Example 2.1, what is the AVERAGE velocity of the same object between t = 2.0 s aPer NCERT Example 2.1 (x = a + bt², b = 2.5 m/s²), what is the velocity at t = 2.0 s?