Select which of the following are outside influences that can affect a researcher’s ability to control an experiment. attrition statistical models selection bias Hawthorne effect history sample population maturation

If you touch a hot light bulb and get burned, that is an example of a. radiation b. convection c. conduction

A23 kg log of wood begins from rest, 300 m up a sluice (a water track used to transport logs, think of it as an inclined plane with negligible friction) inclined at 20° to the horizontal. after it reaches the flat waterway at the bottom it collides elastically with a 100 kg block of wood initially at rest near the base of the incline. (a) how long does it take the 23 kg log to travel down the incline? (b) what is the speed of the 23 kg log at the bottom of the incline? (c) what are the velocities of both blocks of wood after the collision? (d) what is the total kinetic energy before the collision? (e) what is the kinetic energy of the 23 kg log after the collision? (f) what is the kinetic energy of the 100 kg block of wood after the collision? (g) what is the total kinetic energy after the collision? (h) compare the total initial and total final kinetic energies. is this consistent with what you would expect for elastic collisions? explain!

Answer as quick as ! kate is working on a project in her tech education class. she plans to assemble a fan motor. which form of energy does the motor convert most of its electric energy into? a. light energyb. motion energyc. sound energyd. thermal energy