Pratt & Whitney R-2800 Double Wasp Cutaway From The Military Aviation Museum In Virginia Beach, VA

3.5" Hard Drive Disassembled[960x717]

Source: http://imgur.com/zYzQJZ8

Constant-velocity joints (aka homokinetic or CV joints) allow a drive shaft to transmit power through a variable angle, at constant rotational speed, without an appreciable increase in friction or play. They are mainly used in front wheel drive vehicles, and many modern rear wheel drive cars with independent rear suspension typically use CV joints at the ends of the rear xle halfshafts and increasingly use them on the propshafts (drive shafts).

Use these 90% of the time.

HP 35 Calculator by Twylo on Flickr.

This photo illustrates the excellent insulating properties of aerogel. The crayons on top of the aerogel are protected from the flame underneath, and are not melting. [369x441]

Source: https://openpics.aerobatic.io/