Charlie writes the steps shown to describe the use of a transistor in a closed circuit with flowing current.
using a transistor to amplify a signal
1. current (i1) flows from the base to the emitter.
2. an input causes a small increase in voltage across the base and emitter.
3. i1 increases a small amount.
4. current (i2) flowing from the emitter to the collector changes a large amount.
which change corrects the error in his steps?
change the title to “using a transistor as a switch.”
change step 1 to say that no current flows in the transistor at the start.
reverse the sizes of the changes in current in steps 3 and 4.
reverse the direction of current in step 4.

firearm identification is the process of analyzing the bullets and cartridge cases left at a crime scene to determine if they came from a particular firearm. marks on the bullets and cartridges may be common to every firearm of that type. these are called class characteristics.

it's when something is going so fast it makes a loud noise, breaking the sound barrier, for example: a jet makes a loud noise, not only cause of the jet but because they reached a point where they went so fast that you can year the noise from various parts, kinda like a police car, lets say the car was going   so fast that you hear the siren of the cop car right next to you, but the car is probably a mile a way, it's cos the siren was next to you a few seconds if you understand me