newtons to kilograms-force

A ton of force — what we really measure in newtons

Headlines talk about "a ton of impact force," and seatbelt makers about "hundreds of kilograms of pressure." To a physicist, that confuses mass with force. Here is what a newton really means, why a stiletto heel is more dangerous than an elephant, and where the force that can shatter a phone — or save your life in a crash — actually comes from.