Problems
1. a body of mass 1kg suspended from a spring of negligible mass is found to stretch
the spring by 10cm.
a. what is the spring constant?
b. what is the period of oscillation of the body, if the motion is shm?
c. if the mass is doubled, what is the period of oscillation of a body?

Which of the following is part of the explanation or description of electromagnetic waves? (select all that apply) a. electrically charged molecules in a medium transfer their energy to nearby electrically charged molecules. b. a changing electric field causes a changing magnetic field. c. magnetic molecules in a medium transfer their energy to nearby magnetic molecules. d. a changing magnetic field causes a changing electric field.