Six months for the projectile to encyst before the knees can be opened safely. 有六个月时间让弹片结成胞囊,在膝头上动手术才能安全。
Thus under the condition of without component as sembling diagram, solve the problem of assembling projectile weaving machine with knock-down parts. 从而解决了在没有零件装配图的情况下,装配散件片梭织机的问题。
A projectile with ground-air rocket by the burst of TNT has been designed for dispersing metaldehyde (MA) into the clouds on a large scale. 为了地面利用小火箭有效地对云大量撒播介乙醛,我们设计了一种用TNT分散介乙醛的药桂。
Based on the principle of compound pendulum,the measurement method and corresponding equipment for the centroidal deviation and the rotary inertia of rocket projectile were described. 基于复摆原理,阐述了箭弹的质偏和转动惯量的测量方法及装置,推导出了质偏和转动惯量的计算公式。
On condition that the front body shape of the projectile is unchangeable,a formula is obtained for determining the relation between the optimum boattail angle and the supersonic flight region. 在弹丸前体外形和外界大气密度不变的条件下,提出了利用弹丸炮口马赫数和顶点马赫数确定旋转弹丸最佳尾锥角的方法。
If the incoming projectile were a white dwarf—a superdense star that packs the mass of the sun into a body a hundredth the size—the residents of Earth would be treated to quite a fireworks show. 如果接近的天体是一颗白矮星(whitedwarfstar,一种超密恒星,质量约等同于太阳,但其体积却不到太阳的百万分之一),那麽地球上的居民将可以看到一场壮丽的烟火秀。
另外也有用压缩气体来当作物体的动力,吹箭和气动步枪就是一例。然而大多数的枪枝都是利用化学反应来产生大量气体推进,Light gas guns就是属于此类型。在军事方面,有些抛射物的飞行是利用喷射引擎或是火箭引擎。
英语百科
Projectile 抛体运动
A projectile is any object thrown into space (empty or not) by the exertion of a force. Although any object in motion through space (for example a thrown baseball) may be called a projectile, the term more commonly refers to a ranged weapon. Mathematical equations of motion are used to analyze projectile trajectory.