Please I need just the answers no working needed

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Cell membranes contain channels that allow ions to cross the phospholipid bilaycr. Suppose that a particular potassium channel carries a current of 2.0 pA. How many potassium ions (K+) pass through it in 1.0 ms? In a wire, 7.15 x 10 electrons flow past any point during 3.05 s. What is the magnitude / of the current in the wire? I = AIn a wire with a 2.43 mm2 crosssectional area, 8.31 X 1020 electrons ew past any point during 2.29 5. What is the current I in the wire? Determine the current density[ J. A wire has a current density of "LS? x 106 Nmz. If the crosssectional area of the wire is 1.55 mmz, what current I does the wire carry? With this current, how much time t is required for 3.93 X 1020 electrons to pass any point on the wire? '2 s : Find the drift velocity vd of conduction electrons in a gold wire of diameter l.30 mm when a current of 0.23"; A ows in it. The density of conduction electrons in gold is 5.90 x 1023 rn'3. When a current ows in an aluminum wire of diameter 4.49 mm, the drift speed of the conduction electrons is 0.000265 mfs. How many electrons are owing past a given point each second? The conduction electron density in aluminum is 6.00 x 1013 m3. I What is the resistance R of a 54-5mlong aluminum wire that has a diameter of 8.6? mm? The resistivity of aluminum is 2.83 x 10-3 9-111. How long L is a tungsten wire if it has a diameter of 0.187 x 10 m and a resistance of 3.31 ko? The resistivity L = m of tungsten is 5.62 x 10-8 2.m.Two insulated copper wires of similar overall diameter have very different interiors. One wire possesses a solid core of copper, with a circular cross section of radius 3.78 mm. The other wire is composed of 19 strands of thin copper wire bundled together. Each strand has a circular cross section of radius 0.756 mm. The current density J in each wire is the same. D J = 2150 A/m2 How much current does each wire carry? solid wire current: A stranded wire current: A The resistivity of copper is p = 1.69 x 10-2.m. What is the resistance of a 3.25 m length of each wire? solid wire resistance: stranded wire resistance:A certain single ion channel is selectively permeable to K+ and has a resistance of 1.15 GB. , therefore a current of potassium ions through the channel is possible. During an experiment, the channel is open for approximately 1.50 ms while the voltage across the channel is maintained at 95.5 mV. How many K+ ions, N , travel through the channel during this time? You measure the current through a 35.9 2 resistor to be 425 mA. What is the potential difference across the contacts of the resistor? potential difference: VThe maximum allowed power dissipation for a 23.1 2 resistor is stated to be 10.0 W. Calculate the largest current that this resistor can take safely without burning out. largest safe current: A. A 1 100 W toaster takes one minute to toast :1 slice of bread. At 9.0 cents! (kW-h} . how.r much does the toast cost? Giant electric eels can deliver a voltage shock of 5.00 x 102 V and up to LOCI A of current for a brief time. What is the maximum power a giant electric eel can deliver to its prey[ during this time? The body of a snorkeler swimming in salt water has a resistance of about 5T5 Q. If the snorkeler is unfortunate enough to be struck by the eel. what current will ow through her body? current: A A current of about 500 mA can cause heart brillation and death if it lasts too long. Is the current through the swimmer in this case large enough to be dangerous? 0 yes O no What power does the snorkeler receive from the eel? What current / is needed to transmit 115 MW of power over a transmission line held at a voltage of 25.0 k V? I = A Find the power loss Ploss that would occur in the transmission line if a 1.55 2 line is used to transmit 115 MW of power. Ploss = W What percent loss does this represent? percent loss: %