The power of lenses used in the spectacles of a person are -2.5 D and +4.0 D respectively. What are the focal lengths and nature of lenses?

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Ais useful when you need a simple machine to you separate two things. a. lever b. screw c. pulley d. wedge

Apersons beliefs and general outlook, which act like filters on the information they receive are called ?

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.