SI unit of force, equal to the force needed to accelerate 1 kg at 1 m/s2
1 N = 1 kg-m/s2
named after Isaac Newton, who formulated the laws of motion and universal gravitation
weight of a 1 kg mass on Earth: ~9.81 N
Newton's second law: F = m * a, the defining relation
connects to joule (1 J = 1 N-m), pascal (1 Pa = 1 N/m2), and watt (1 W = 1 N-m/s)
a typical apple weighs about 1 newton
forces in engineering range from micronewtons (MEMS devices) to meganewtons (rocket thrust)