1. Particles with a charge of +3e are incident on a target. If the beam of particles carries a current of 111 µA, how many particles strike the target in a period of 30.0 s? 2. What is the fractional change in the resistance of an iron filament when its temperature changes from 21.4°C to 50.4°C (the 2 questions are not related)

1. A tungsten wire has a radius of 0.072 mm. When 128 V is applied across the ends of the hot wire, a current of 3.00 A is produced. How long is wire? (The resistivity of tungsten is 2.65 × : m 5 cci16 cm) ceil6 ceil6 cc

3. Look up tabulated conductivities (or resistivities) of copper, silver, and aluminum at 20 °C and calculate the resistance of a copper wire that is 2 meters long with a1 mm diameter. Repeat your calculation for silver, and for aluminum. The density of free electrons is 8.5x1028 particles/m3 for copper, 5.86x 102 m-3 for silver, and 18.1x1028 m-3 for aluminum. For a potential difference of 5 volts, how do the electron drift velocities in each of the three wires compare with one another?

An iron wire has a resistance of 78.7. m ohm at 20 degrees Celsius. When the wire carries a current, the heat generated by the current causes the temperature of the wire to rise by 22 degrees Celsius. What is the change in the resistance of the wire? If its final current was 56.2 mA. what is your original current?

1. The current supplied to an air conditioner unit is 4.5 amps. The air conditioner is wired using a 10- electrons gauge (diameter 2.588 mm) wire. The charge density of the wire is n= 8.48 1028 m³ Find the magnitude of (a) current density and JD m² (b) the drift velocity. S. <飞

8. A heating element using nichrome connected to a 230 V supply draws an initial current of 3.2 A which settles after a few seconds to a steady value of 2.8 A. What is the steady temperature of the heating element if the room temperature is 27.0°C? Temperature coefficient of resistance of nichrome averaged over the temperature range involved is 1.70× 10 °C-1. -4

please answer this question

Particles with a charge of +2e are incident on a target. If the beam of particles carries a current of 128 µA, how many particles strike the target in a period of 27.0 s?

5. A small bulb is rated at 7.5 W when operated at 125 V. The tungsten filament has a temperature coefficient of resistivity a= 4.5×10/°C.When the filament is hot and glowing, its temperature is seven times room temperature (20 °C). What is the resistance of the filament (in ohms) at room temperature? ANS = 1350

2 What is the SI unit of resistance? A Ω V F In solid metals, which charged particles are free to move throughout the object? Select any/all correct answers. protons neutrons electrons 4 Which factor(s) affect the current in a conductor? Select any/all correct answers. cross-section area density of the charged particles drift speed of the charged partiçles