Lever escapement "draw" its action is very precise. Third, it is self-starting, so if the watch is jarred in use so the balance wheel stops, it will start again. A cheaper and less accurate version of the lever escapement, called the pin pallet escapement, invented by Georges Frederic Roskopf in 1867, is used in clocks and timers. The escape wheel is geared to the watch's wheel train, which applies torque to it from the mainspring. The rotation of the escape wheel is controlled by the pallets. The escape wheel has specially shaped teeth of either ratchet or club form, which interact with
Mechanical energy mechanical energy of the colliding objects has been converted into an equal amount of heat. Thus, the total energy of the system remains unchanged though the mechanical energy of the system has reduced. A satellite of mass formula_4 at a distance formula_5 from the centre of Earth possesses both kinetic energy, formula_6, (by virtue of its motion) and gravitational potential energy, formula_7, (by virtue of its position within the Earth’s gravitational field; Earth's mass is formula_8). Hence, mechanical energy formula_9 of a satellite is given by If the satellite is in circular orbit, the energy conservation equation can be further