Hai quả cầu kim loại mang các điện tích lần lượt là q1 q2 cho tiếp xúc nhau. Sau đó tách chúng ra thì mỗi quả cầu mang điện tích gì

"an open tank has the shape of a right circular cone. the tank is 6 feet across the top and 5 feet high. how much work is done in emptying the tank by pumping the water over the top edge? note: the density of water is 62.4 lbs per cubic foot."

Acompound machine is also called a machine. a. force b. simple c. complex d. directional

Acar jack with a mechanical advantage of 6 needs to produce an output force of 600 n to raise a car. what input force is required? 6 n 100 n 600 n 3,600 n