An 8.0-newton wooden block slides across a horizontal wooden floor at constant velocity. what is the magnitude of the force of kinetic friction between the block and the floor? (1) 2.4 n (3) 8.0 n (2) 3.4 n (4) 27 n

When you push downward on a book at rest on a table, you feel an upward force. does this force depend on friction? defend your answer.

Cells in the nervous system have a potential difference of 70 mv across the cell membrane separating the interior of the cell from the extracellular fluid. this potential difference is maintained by ion pumps that move charged ions across the membrane. is this an emf? select the correct answer and explanation. 1)no. the ion pumps cannot separate charges; thus, they cannot create a potential difference. 2)yes. the ion pumps cannot separate charges, but they still can create a potential difference. 3)yes. the ion pumps can actively separate charge; thus, they can create a potential difference. 4)no. the ion pumps can separate charges, but they cannot create a potential difference.

The place where two plates come together is known as a a. transform boundary. b. divergent boundary. c. convergent boundary. d. rift valley.