英文物理题(牛二律)An 92 N box of oranges is being pushed across a horizontal floor.As it moves,it is slowing at a constant rate of 0.80 m/s each second.The push force has a horizontal component of 40 N and a vertical component of 45 N dow

来源:学生作业帮助网 编辑:六六作业网 时间:2024/11/26 15:06:52
英文物理题(牛二律)An92Nboxoforangesisbeingpushedacrossahorizontalfloor.Asitmoves,itisslowingataconstantrateo

英文物理题(牛二律)An 92 N box of oranges is being pushed across a horizontal floor.As it moves,it is slowing at a constant rate of 0.80 m/s each second.The push force has a horizontal component of 40 N and a vertical component of 45 N dow
英文物理题(牛二律)
An 92 N box of oranges is being pushed across a horizontal floor.As it moves,it is slowing at a constant rate of 0.80 m/s each second.The push force has a horizontal component of 40 N and a vertical component of 45 N downward.Calculate the coefficient of kinetic friction between the box and floor.

英文物理题(牛二律)An 92 N box of oranges is being pushed across a horizontal floor.As it moves,it is slowing at a constant rate of 0.80 m/s each second.The push force has a horizontal component of 40 N and a vertical component of 45 N dow
工科留学生为你解答.
分析
由slowing at a constant rate of 0.80 m/s each second可知其加速度为-0.80m/s^2.
因为盒子的重量为92N,其质量就是92N/g=460/49kg.由F=ma可知,盒子所受合力为-0.8*460/49 N=-368/49N.
合力是水平方向产生的(竖直方向受力始终平衡),合力即摩擦力和推力的矢量和:F=T+f,可得f=F-T=-368/49N-40N=-2328/49N
摩擦力和摩擦系数的关系:f=μN,即μ=f/(G+Nv)=|2328/49/(92+45)|=2328/6713=0.347
a=Δv/Δt=-0.8m/s /1s=-0.8m/s^2;
m=G/g=92N/(9.8m/s^2)=460/49kg;
F=ma=-0.8m/s^2*460/49kg=-368/49N;
f=F-T=-368/49N-40N=-2328/49N;
μ=f/(G+Nv)=|2328/49N/[(92+45)N]|=2328/6713=0.347.

物体做减速运动,加速度是0.8m/s^2
F=ma=(92/9.81)*0.8
F=40-45*f
这样就可以算出摩擦系数了

英文物理题(牛二律)An 92 N box of oranges is being pushed across a horizontal floor.As it moves,it is slowing at a constant rate of 0.80 m/s each second.The push force has a horizontal component of 40 N and a vertical component of 45 N dow 英文中Bo 关于力的一道物理题.如图,两根轻绳AO、BO栓一个重为20N的木块,AO=BO=AB,求:绳AO、BO的拉力有多大? [高一物理题]用绳AO和BO吊起一个重100N的物体1.如图所示,用绳AO和BO吊起一个重100N的物体,两绳AO、BO与竖直方向的夹角分别为30o和40o,求绳AO和BO对物体的拉力的大小. 2.如图所示,重力为500N的人通 我经常做物理题(英文) 一道大学物理题(由于小弟英语授课)英文题目Two small,positively charged spheres have a combined charge of 2.5×10-5C.If each sphere is repelledfrom the other by an electrostatic force of 1N when thespheres are 2 m apart,what is th 一道英文(sat2)物理题 薄(bo)组词 卜(bo) bo 又一道物理题,英文版,Consider an electron trapped in an infinite well whose width is 98.5pm .If it is in a state with n=15,what are (a)its energy(b)The uncertainty in its momentum(c)The uncertainty in its position.最好有个方程,好看 在{an}中an>0 Sn=1/2(an+n/an)求an 问两道英文物理题.1、An 819 N bungee jumper falls from a bridge that is 674 x 10-1 m high. The force constant of the bungee cord is 1.50 x 101 N/m, and its unstretched length is 7 m. How far above the ground is the jumper, when he reaches a s 已知数列{an}中a1=6,且an-an-1=(an-1/n)+n+1(n属于N*,n≥2),求an 一道中学物理题(英文表述)A charged sphere is placed inside a metal container by an insulated thread.The container is earthed .Which of the diagranms shows the distribution of charges correctly? 物理题电灯的重力电灯的重力G=10N,AO绳与顶板间夹角为45°,BO绳水平,则AO绳所受的拉力F1,BO绳所受的拉力F2分别是多大... 已知数列An中满足An-2/An=2n.且An是An-(2/An)=2 已知A1=1,An=2An-1+n(n>1),求An.