当物体做曲线运动时,加速度可以分解为沿着速度方向的切向加速度和垂直于速度方向的向心加速度,切向加速度改变速度的大小,向心加速度改变速度的方向.当物体做匀速圆周运动时,速度的大小将不发生变化.只存在改变速度方向的向心加速度,向心加速度的作用是只改变速度的方向.从加 When the object curves, the acceleration can be decomposed into a tangential acceleration along the speed direction and a centripetal acceleration perpendicular to the speed direction. The tangential acceleration changes the speed and the centripetal acceleration changes the speed direction. When the object makes a uniform circle Movement, the size of the speed will not change. There is only to change the direction of the centripetal acceleration, centripetal acceleration only changes the direction of the speed. From