Three Newton's-second-law rows hold acceleration fixed while mass changes, exposing force as the scaled output.
Example
With acceleration fixed, Newton's second law makes force scale with mass. Exact arithmetic here means exact results for the stated model inputs; measured inputs still carry uncertainty and significant-figure limits.
highlighted = computed this step
Hold acceleration fixed and scan mass
Newton's second law is a scaling rule: more mass needs more force for the same acceleration.
F=ma
Light cart
Mass 1 kg at the fixed acceleration needs 3 N.
F=ma=1kg⋅3m/s2=3N
Middle cart
Mass 2 kg at the same acceleration needs 6 N.
F=ma=2kg⋅3m/s2=6N
Heavy cart
Mass 3 kg at the same acceleration needs 9 N.
F=ma=3kg⋅3m/s2=9N
The force column follows mass
Acceleration is held fixed, so doubling mass doubles the required net force; tripling mass triples it.
m1kg2kg3kga3m/s23m/s23m/s2F3N6N9N
mechanicsAt 3 m/s squared, masses 1 kg, 2 kg, and 3 kg require net forces 3 N, 6 N, and 9 N.