4-blade rotating glass solar-powered windmill 3*5.3 inches

Description de 4-blade rotating glass solar-powered windmill 3*5.3 inches

A beautiful glass radiometer, a great gift. Compatible with those who have everything.

It is made entirely of glass. The sphere is 7.6 cm in diameter and 13.7 cm high.

This physical and technical marvel clearly shows you how sunlight is converted into energy.

Place it near a window or under a light bulb and watch the blades rotate.

Invented in 1873 by chemist Sir William Crookes as a by-product of chemical research, the radiometer is made of a glass bulb from which much of the air has been removed to create a partial vacuum. Inside the bulb, on a low-friction spindle, is a rotor with several (usually four) vertical metal blades evenly spaced around the circumference. The blades are polished or white on one side and black on the other. When the blades are exposed to sunlight, artificial light or infrared radiation (even the warmth of a nearby hand is enough), the blades rotate without any apparent driving force, the dark sides recede from the radiation source and the light sides advance. Just place it near a window or under direct incandescent light, as the blades rotate only in light (sunlight or incandescent light). The more light shines on the sphere, the faster the blades rotate.

Color: Photo color

Material: Glass

Type: A: Blue base

Package Contents:

1x 4-blade rotating glass windmill

Only the above package contents, other products are not included.

Note: Light reflection and different displays may cause the color of the item in the picture to be slightly different from the real thing. The measurement allowed error is +/- 1-3 cm.