A copper wire has radius 0.800 mm and carries current I at20.0°C. A silver wire with radius 0.500 mm carries the same current andis also at 20.0°C. Let ECu be the electric field in the copper wire and EAgbe the electric field in the silver wire. What is the ratio ECu/EAg?

Consider a wire made of copper with conductivity 6.0 × 107 £¯¹m³¹, which has a circular cross-section of radius 0.56 mm. In a particular circuit, this wire carries a current of 4.5 A. What is the electric field, in volts per meter, inside this wire? If we replace this wire with a gold one of the same size, with conductivity 4.1 × 107 ¹m-¹, what will the electric field in the wire be?

8 - The figure in the attachment represents a section a circular conductor of nonuniform diameter carrying a current of 6 A. radius of cross section A1 is 0.5 cm. What is the magnitude of the current density across A,? Ag A1 Figure P27.8 a) O 50,64 kA/m? b) O 56,4 kA/m2 c) O 76,4 kA/m2 d) O 76 A/m² O 56,4 A/m?

A charge crossing a surface due to a proton beam is given by Q = 5.0t3 + 3.0t2 + 8.0 where Q is measured in Coulombs and the time t is measured in seconds. What is the current due to the proton beam when t = 3.0 s. О (а) 459 A О (b) 153 А O (c) 297 A O (d) 99 A O (e) 56.7 A