What is an action potential? a) chemicals released by glands b) atp generated by the sodium/potassium pump c) neurotransmitters that travel from the end of the axon to an effector d) electrical signals that are generated by the movement of ions across the cell membrane of a neuron

Alightning strike consists of charge moving from a cloud to the ground . in one particular case, the electrons in a lightning strike are confined to travel within a radius of 1.5 m and to move at a speed of 5.0 x 10 m/s. if the density of electrons in the strike is 10'15 electrons/m what current is carried by the lightning ?

Modern physics a photon emitted from an excited hydrogen atom has an energy of 3.02 electron volts. which electron energy-level transition would produce this photon? a. n=1 to n=6 b. n=2 to n=6 c. n=6 to n=1 d. n=6 to n=2 i chose b but the correct answer is d can someone tell me why? and what's the difference?

Given the position vector of the particle r(t)=(t+1)i+(t^2−1)j+2t k, find the particle's velocity and acceleration vectors at t=1