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 o):

Ok i am attempting to my niece attach a galvanized wire (like a tether for a dog) at the corner of two fences, making a tightwire if you will and we drilled a hole in a softball and she hits it. the ? and problem is that we can not get the wire taunt enough where it doesnt sag after hitting the ball once, and the wire sags and wobbbles. its a 15 ft rubber covered galvanized wire and one can adjust the length of the placing of the wire by having it make the corner of 2 fences become a it can be adjusted, however, with all our human strength and pliers we could not make it taunt as possible. is there anything other that attaching it to a car to do this. sorry abt the length but it would mean the world to my niece if i could solve this came up with the entire idea herself, and she is 14 and paid for the wire and did as much work as i did drilling a hole through a softball wide enough for attaching piece at each end of the wire that clips on to the fence. . any ideas welcome if serious. but awesome if it is a fact. much obliged. bucky bukowski buckman

Order the sequence of ideas that lead to marie curies discovery of radioactive elements number the events in chronological order starting with the oldest

Why don't you see your reflection in water with waves or repples