An unglazed piece of porcelain, used to test the characteristic streak of minerals by rubbing the mineral across the tile. Streak plates have a hardness of about 6.5 on the Mohs scale and cannot be used for testing harder minerals.
Birds are warm-blooded, which means they need to move and eat more in the cold to stay warm; snakes are cold-blooded, so they don't have to.
<span>The formula for frequency is speed of light divided by wavelength. 650 nm represents the wavelength and 3x10^8 m/s is the speed of light. If you convert 650nm to meters you get 6.5x10^-7 m so you can divide using the formula above, giving you 4.6x10^14 1/s or Hz, the unit of frequency in Physics.</span>
Answer:
X: Use DC
Y: Use AC
Explanation:
The objects: Wall clock, T V remote control, Portable music player, are normally powered by batteries, which run DC current.
On the other hand, the objects: Refrigerator, Table lamp, Hair dryer, demand much larger power, and are normally run from the AC plug on the wall.
