It’s possible to estimate the percentage of fat in the body by measuring the resistance of the upper leg rather than the upper arm; the calculation is similar A person’s leg measures 40 cm between the knee and the hip, with an average leg diameter (ignoring bone and other poorly
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- current of 0.080 A passing through a human body could be fatal. If you accidentally touched a 110 V supply,what skin resistance will produce a current of 0.080 A?arrow_forwardA 100 μF defibrillator capacitor is charged to 1500 V. When fired through a patient's chest, it loses 95% of its charge in 40 ms. What is the resistance of the patient's chest?arrow_forwardSuppose that the resistance between the walls of a biological cell is 1.10 1010 Ω. (a) What is the current when the potential difference between the walls is 50 mV?arrow_forward
- The potential difference across the terminals of a battery is 8.1 V when there is a current of 1.51 A in the battery from the negative to the positive terminal. When the current is 3.44 A in the reverse direction, the potential difference becomes 9.7 V . What is the internal resistance of the battery and What is the emf of the battery?arrow_forwardA gold wire carries 24.5 A of current with a drift velocity of 2.5 × 10-3 m/s. Assume there is one free electron per gold atom, and the density of gold is 1.93 × 104 kg/m3. The molecular weight of gold is 196.97 g/mol. Part (a) What is the diameter of this gold wire? d = m Part (b) For the problem above, calculate the resistance of the wire under those conditions. Assume the wire is 3.8 m in length, and the resistivity of gold is 2.44 × 10-8 Ω⋅m. R = Ω Part (c) How much power is dissipated by this wire? P= W Part (d) If the wire is heated by an additional 89 K (compared to part (a)), what is the new resistance at this increased temperature? The temperature coefficient of resistivity for gold is 3.4 × 10-3 °C-1 R = Ω Part (e) Under the conditions in part (d), what is the value of the potential for the wire? V =…arrow_forwardAn aluminum wire having a cross-sectional area of 3.90 x 10-6 m² carries a current of 3.00 A. The density of aluminum is 2.70 g/cm³. Assume each aluminum atom supplies one conduction electron per atom. Find the drift speed of the electrons in the wire. X 0.798 The equation for the drift velocity includes the number of charge carriers per volume, which in this case is equal to the number of atoms per volume. How do you calculate that if you know the density and the atomic weight of aluminum? mm/sarrow_forward
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