Một electron bay vào trong từ trường đều theo phương vuông góc với các đường sức từ với tốc độ 1,6.106 m/s. Lực Lorentz tác dụng lên electron có giá trị 1,6.10– 16 N. Biết chiều của vận tốc v⃗⃗ và lực F⃗⃗ như hình vẽ. Tính độ lớn cảm ứng từ B và vẽ hướng của các đường sức.

An athlete is holding 24 lb of weights at a height of 6 inches above the stack as shown. to lower the weights, she applies a constant force of 5 lb to the handle. determine the velocity of the weights immediately before they hit the stack.

Why does lightning travel from clouds to the ground?

On a horizontal frictionless surface, a small block with mass 0.200 kg has a collision with a block of mass 0.400 kg. immediately after the collision, the 0.200 kg block is moving at 12.0 m/s in the direction 30° north of east and the 0.400 kg block is moving at 11.2 m/s in the direction 53.1° south of east. use coordinates where the +x-axis is east and the +y-axis is north.(a) what is the total kinetic energy of the two blocks after the collision (in ) what is the x-component of the total momentum of the two blocks after the collision? (indicate the direction with the sign of your ) what is the y-component of the total momentum of the two blocks after the collision? (indicate the direction with the sign of your answer.)