The potential difference across the terminals of a battery is 8.40 V when there is a current of 1.50 A in the battery
from the negative to the positive terminal. When the
current is 3.50 A in the reverse direction, the potential
difference becomes 10.20V. (a) What is the internal
resistance of the battery? (b) What is the emf of the
battery?

Suppose that a mass of 2 kg is attached a spring whose spring constant is 50. the system is damped such that b = 12 . the mass is set in motion with an initial velocity of -8 m/s at a position 0 meters from equilibrium. set up and solve a differential equation that models this motion. write your solution in the form a cos ( ω t − α ) where α is a positive number. use your solution to fill in the information below: what is the amplitude of the motion? what is the value of ω ? what is the phase shift?