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原题.(2003年全国理综卷第25题)两根平行的金属导轨,固定在同一水平面上,磁感应强度B=0.50 T的匀强磁场与导轨所在平面垂直,导轨的电阻很小,可忽略不计,导轨间的距离l=0.20 m.两根质量均为m=0.10 kg的平行金属杆甲、乙可在导轨上无摩擦地滑动,滑动过程中与导轨保持垂直,每根金属杆的电阻为R=5.0Ω.在t=0时刻,两金属杆都处于静止状态,现有一与导轨平行、大小为0.20 N的恒力F作用于金属杆甲上,使金属杆在导轨上滑动.经t=5.0 s,金属杆甲的加速度为a=1.37 m/s~2,问此时两金属杆的速度各为多少?
(2003 National Volume 25) Two parallel metal rails, fixed at the same level, the magnetic flux density B = 0.50 T uniform magnetic field perpendicular to the plane where the guide rail, rail resistance is small, can be Neglected, the distance between the rails is l = 0.20 m. Two parallel metal bars with mass m = 0.10 kg, B can slide on the rail without friction, perpendicular to the guide during sliding, and each metal bar The resistance is R = 5.0Ω. At t = 0, both metal rods are at rest and a constant force F parallel to the guide rail of 0.20 N is applied to the metal rod A, causing the metal rod to slide on the rail. After t = 5.0 s, the acceleration of the metal armor a = 1.37 m / s ~ 2, asked at this time how much the speed of the two metal rods?