Part A You need to design a 1.4 A fuse that "blows" if the current exceeds 1.4 A. The fuse material in your stockroom melts at a current density of 510 A/cm?. What diameter wire of this material will do the job? Express your answer to two significant figures and include the appropriate units. HA ? D= 6.2 • 10¯2 cm Submit Previous Answers Request Answer X Incorrect; Try Again; 4 attempts remaining Review your calculations and make sure you round to 2 significant figures in the last step. Provide Feedback

Part A A length of aluminum wire is connected to a precision 10.00-V power supply, and a current of 0.4192 A is precisely measured at 23.5 °C. The wire is placed in a new environment of unknown temperature where the measured current is 0.3698 A . The temperature coefficient of resistivity of aluminum is 0.00429 (°C)-1 What is the unknown temperature? Express your answer using three significant figures. να ΑΣφ ? T = °C Submit Request Answer Provide Feedback

A conductor has a circular cross-sectional area A, length L, and L resistivity p, as shown. A Suppose you want to double the resistance of the conductor. Would the following changes achieve this goal? i) Yes No Replace the conductor with one made from a material with half the resistivity, keeping everything else the same: ii) Replace the conductor with one made from a material with half the conductivity, keeping everything else the same: Yes No Double the length of the conductor, keeping everything else the same: iii) Yes No Double the radius of the conductor, keeping everything else the same: iv) Yes No Yes Reduce the radius of the conductor by half, keeping everything else the same: v) No

A material is formed into a long rod with a square cross-section 0.50 cm on each side. When a 112 VV voltage is applied across a 20-mm length of the rod, a 4.0 AA current is carried.     Part A What is the resistivity of the material? Express your answer using two significant figures.