AP Phyics物理1)A 5-kg mass resting on a smooth horizontal table is connected to a cable which passes over a pulley and then is fastened to a hanging 10-kg mass as shown.Find the acceleration of the two objects and the tension in the string.2)A baseball is hit in such a way that the ball just clears a wall 3m tall,130m from home plate.The ball leaves at an angle of 35 degrees to the horizontal and 1m above the ground.Find its initial velocity.3) A baseba
AP Phyics物理
1)A 5-kg mass resting on a smooth horizontal table is connected to a cable which passes over a pulley and then is fastened to a hanging 10-kg mass as shown.Find the acceleration of the two objects and the tension in the string.
2)A baseball is hit in such a way that the ball just clears a wall 3m tall,130m from home plate.The ball leaves at an angle of 35 degrees to the horizontal and 1m above the ground.Find its initial velocity.
3) A baseball pitcher throws a fastball horizontally at 42.m/s.How far does it drop before crossing the plate,which is 18.3m away?
题中说如图所示 没图啊..大概翻译下:过程自己翻译过去吧
1.一个质量为5Kg的物体静止放在光滑的水平面上,通过细绳和滑轮与一10Kg的悬垂的物体相连,如图所示.求两个物体的加速度和细绳所受的张力.
设绳子所受张力为F,g的值取10 根据两物体加速度时时相等列等式
可得F=33.3N(100/3) a=6.7m/s2(20/3)
2.一个棒球被击打,球恰好越过一座3m高的墙壁,离起点130m.球的初速度与水平面成35度角,击球点离地面1m.求球的初速度.
(这题有点疑问,是130m吗 还是13m啊 确定是35度吗 应该是特殊角吧30或45)
3.棒球投手以42m/s的速度水平地投球,球在越过18.3m远外的墙之前落在多远处
落下
（可能我的理解有问题,before crossing the plate,which is 18.3m away这个条件不知怎么用）