英语翻译1.what is the formula for momentum,and is it a vector?2.

英语翻译
1.what is the formula for momentum,and is it a vector?
2.Briefly state Newton's Third Law.
3.If a box is sliding to the right,direction is the force of friction on the box?
4.Name one difference between mass and weight.

1.动量公式是什么,它是矢量吗?
动量：p＝mv ｛p:动量(kg/s),m:质量(kg),v:速度(m/s),方向与速度方向相同｝ ,是矢量.
Momentum:p = mv (p:momentum (kg / s),m:mass (kg),v:velocity (m / s),direction and speed in the same direction) is a vector.
2.简述牛顿第三定律.
牛顿第三定律：两个物体间的作用力和反作用力总是大小相等,方向相反,并且作用在同一直线上 .F1＝－F2
①力的作用是相互的.同时出现,同时消失.
②相互作用力一定是相同性质的力
③作用力和反作用力作用在两个物体上,产生的作用不能相互抵消.
④作用力也可以叫做反作用力,只是选择的参照物不同
⑤作用力和反作用力因为作用点不在同一个物体上,所以不能求合力
Newton's Third Law:the force between two objects and reaction are always equal and opposite,and the role of a straight line.F1 =- F2
① force's role is mutual.Also appear at the same time disappear.
② interaction force must be of the same nature
③ reaction force and the role of the two objects,the resulting effect can not cancel each other out.
④ called the reaction force can only choose different reference
⑤ force and reaction force acting point is not the same as an object,it can not seek together
3 如果一个箱子向右侧滑动,求摩擦力的方向?
左
Left
4 陈述一下质量和重量的一点区别
1．定义不同.质量是物体惯性的量度,它是任何物体都固有的一种属性.重量则反映了物体所受重力的大小,它是受地球的吸引而引起的.
2．质量是标量.重量是矢量.
1.Different definition.Quality is the measure of inertia an object,any object which is an inherent property of all.Suffered weight reflects the gravity of the size of the object,it is attracted by the Earth caused.
2.Quality is the scalar.Weight vector.