Crookes Radiometer
Capture the Interest of Students With This Classical Piece of Equipment
Show the effect of differential absorption of radiation and expansion of residual gas. A rotating shaft inside the 99%-evacuated glass globe has four attached vanes. Each vane has a black face and a whit face. Illuminate the bulb with an ordinary incandescent light. Watch the vanes spin as the black sides absorb more heat than the white ones, and thus expand the neighboring gas at a greater rate.
熱輻射計
這是一個示範吸收不同的輻攝和氣體擴散的裝置。一中空玻璃圓柱
裡有一有四個槳的轉軸。每一槳上有一面是白的一面是黑的。在裝
置旁放一照明用具,當槳的黑色面吸收比白色面更多的熱時便開始轉
動,並使旁邊的氣體以較快的速率擴散。