A firefighter uses a heavy-duty crowbar to pry open a jammed door. The firefighter applies a perpendicular force of 85.0 N85.0\text{ N}85.0 N to the end of the crowbar at a distance of 0.64 m0.64\text{ m}0.64 m from the pivot.
State the equation linking moment, force and perpendicular distance from the pivot.
Calculate the moment of the force applied by the firefighter on the crowbar and give the unit.
The firefighter then tries using a more compact crowbar. On this compact tool, the force is applied at a distance of only 0.40 m0.40\text{ m}0.40 m from its pivot. Explain why the minimum force required to open the same jammed door using this compact crowbar is greater than 85.0 N85.0\text{ N}85.0 N.