v-t图象可以形象直观地反映物体的运动规律。一、用v-t图象讨论“子弹打木块”问题例1如图所示质量为m的子弹以水平速度v_0射向放在水平地面上的木块。木块长为L,质量为M,设木块对子弹的阻力恒定,子弹射穿木块后获得速度为v。若改变木块或子弹的质量,但子弹的初速度、所受阻力和木块长度不变,并且 v-t image can visually reflect the object’s movement law. First, use the v-t image to discuss the “bullet hit the wood” Problem Example 1 As shown in the mass of m bullets at horizontal velocity v_0 shot on the level of the ground on the wood. The length of the block is L, the mass is M, the resistance of the block to the bullet is set to be constant, and the velocity of the bullet shot through the block is v. If you change the quality of wood or bullets, but the initial velocity of the bullets, the resistance and the length of the block unchanged, and