3 A 15 kg block of ice is being pulled along a rough surface with a force of 45 N.
If the horizontal acceleration of the block is 2.0 m/s2 to the right, what would be magnitude
and direction of the force of friction acting on the block? *
(10 Points)
75 N to the right.
15 N to the left.
90 N to the right.
30 N to the left.

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.