I need to vary the speed of an AC drill (plugs into the wall, 3.5 A), and I bought a 5k ohm, 2W 10 step linear potentiometer (will use as a rheostat). Will connecting it in between the wall allow me to control the speed, or will it kill me?
No, you will smoke the potentiometer. When the pot is at full resistance the drill won't rotate and the pot will be dissipating over 2 watts. As the pot resistance is turned down, it is even more likely to burn up. The drill uses about 400 watts its resistance is 120/3.5 which is about 35Ω. You would need a 50Ω rhoestat that can dissipate 500 + watts.I don't think they make pots with that wattage. And I think as a speed control the variable resistance will cause the drill motor to overheat and burn out. Most speed controllers are done with a semiconductor device called a TRIAC and they use a potentiometer capacitor combination to adjust the firing voltage on the TRIAC's gate. I recommend you buy a variable speed drill, it is the cheapest and best way to go.
It would not work. 5K turns into smoke right away. You need 30 ohm rheostat rated 500w to control it.
Best is to buy a drill with built in speed control. Probably less than $50. Neil
STOP 1. I smell a Darwin Award (Third class) in the making. That motor draws over 300 W. You propose to regulate the current (of 3.5A.), with a 2W. variable transformer? You probably won't get killed but you WILL fry the reostat. 2. In principle you can decrease the torque produced by a motor, and thus speed under a given load, by reducing the voltage WITHIN LIMITS. You also increase the current and AC motor draws as you decrease the voltage, and you can burn out the motor that way. There are cheap solid state VFD fan motor controlers sold at your local hardware store, that will accomplish what you want a lot cheaper and safer. You need one rated for 500W. or more.
No No No. It might not kill you, but it wii probably explode.
