Hai dòng điện có cường độ I1=2A, I2=4A chạy trong hai dây dẫn thẳng dài vô hạn, đồng phẳng, vuông góc với nhau đặt trong không khí.Trong mặt phẳng chứa hai dòng điện, quỹ tích những điểm tại đó vec tơ cảm ứng từ tổng hợp bằng 0 là đường thẳng( trừ điểm gốc tọa độ )):

Why are biogeochemical cycles important? earth is a closed system. that means the amount of rocks, metals, carbon, nitrogen, oxygen, and water on so, it is essential that biogeochemical these materials as they move through earth's subsystems.

Atank holds 1000 gallons of water, which drains from the bottom of the tank in half an hour. the values in the table show the volume v of water remaining in the tank (in gallons) after t minutes.t(min) 5 10 15 20 25 30v(gal) 694 444 250 111 28 0(a) if p is the point (15, 250) on the graph of v, find the slopes of the secant lines pq when q is the point on the graph with t = 5, 10, 20, 25, and 30.(b) estimate the slope of the tangent line at p by averaging the slopes of two secant lines.(c) use a graph of the function to estimate the slope of the tangent line at p. (this slope represents the rate at which the water is flowing from the tank after 15 minutes.)show all steps.

Two technicians are discussing a resistance measurement between the can-h and can-l wires. technician a says this measurement should be done with the ignition switch in the "run" position. technician b states that a measurement of 0 ohms indicates an open in the network. which technician is correct?