Laws of Motion
Class 11 · Laws of Motion
Newton's Second Law
F = ma — apply a force, change the mass, see acceleration respond in real time.
Key Notes
01
F_net = ma — net force equals mass times acceleration.
02
More generally: F = dp/dt where p = mv is momentum.
03
Direction of acceleration = direction of net force.
04
Doubling the force doubles the acceleration; doubling the mass halves it.
Formulas
Second Law
For constant mass.
Momentum form
More general form; applies to variable mass (rockets).
Important Points
Always identify the NET force — sum of all forces — before applying F = ma.
Newton's Second Law notes from sciphylab (also known as SciPhy, SciPhy Lab, SciPhy Labs, Physics Lab). Class 11 physics revision for JEE Mains, JEE Advanced, NEET UG, AP Physics 1/2/C, SAT, and CUET-UG.