Torque
Torque (τ): The rotational equivalent of force. τ = F × d, where d is the perpendicular distance from the pivot (moment arm or lever arm). Measured in Newton-meters (Nm) or foot-pounds (ft-lb).
A longer wrench handle = longer moment arm = more torque with the same force.
Balanced lever: F₁ × d₁ = F₂ × d₂ (effort × effort arm = load × load arm).