Question 8 of 16 A book with a mass of 1.8 kg sits on a bookshelf. If it has a gravitational
potential energy of 42 J, how high is the shelf? The acceleration of gravity is
9.8 m/s2
A. 2.1 m
B. 0.9 m
C. 1.6 m
D. 2.4 m
SUBMIT

What occurs during a combustion reaction

How does an observation about an object differ from an inference about that object

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.