For months, a unit led by Captain Dan Kearney holds an outpost high in the Korengal Valley that gives the soldiers a clear view of the land below, but the impression of force exerted without purpose is overwhelming.

NEWYORKER: Restrepo

Similarly, the pressure exerted by sunlight, and the force exerted by the emissions from each probe's radio antenna, were dismissed: again, both are too weak, and they would tend to push the probes away from the sun, not towards it.

ECONOMIST: A space oddity

Mathematical models are used to simulate the rest of the car, from the gearbox and rear differential to the force exerted by the road, so that the engine is subjected to the same demands and forces as it would be in a real car.

ECONOMIST: Car design

Senssa's rear shell is divided into halves, each of which uses Forcepad technology to calculate the force being exerted upon it.

ENGADGET: Synaptics Sensa grip-sensing tablet concept hands-on

At Oort-cloud distances, the strength of this combined gravity adds up to the same sort of force as that exerted by the solar gravitational field, enfeebled as it is by its remoteness from the sun.

ECONOMIST: X marks the spot