friction is a force that always acts an opposition movementopposition movement又是什么?

friction is a force that always acts an opposition movementopposition movement又是什么? a 4kg body is placed on horizontal ground.The coefficient of dynamic friction between the body and the ground is 0,2.The object is acted upon by a force of 30 N that encloses an angle of 20 with horizontal.Find the friction force and the acceleration 一道英文物理题A 4kg body is placed on horizontal ground.The coefficient of dynamic friction between the body and the ground is 0,2.The object is acted upon by a force of 30 N that encloses an angles of 20 whith horizontal.Find the friction for A 50 kg block of wood is pressed against a smooth wall by a force perpendicular to the wall.If the coefficient of static friction is 0.13 ,what is the minimum force that is necessary to keep the block of wood in place?模糊的翻译:一个50 公斤 You pull horizontally on a 50-kg crYou pull horizontally on a 50-kg crate with a force of 350N and the friction force on the crate is 250N.The acceleration of the crate is 选项A7m/s平方B1m/s平方C12m/s平方D2m/s平方.给评价的 She is a silly force 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. 有没有物理好英语又好的达人帮我看看这些题目?1.If the coefficient of kinetic friction between a 28 kg crate and the floor is 0.25,what horizontal force (in N) is required to move the crate at a constant speed across the floor?2.A p 什么物理实验,目的,原理Static and Kinetic FrictionIf you try to slide a heavy box resting on the floor,you may find it difficult to get the box moving.Static friction is the force that is acting against the box.If you apply a light horizonta 什么物理实验,目的,原理Static and Kinetic FrictionIf you try to slide a heavy box resting on the floor,you may find it difficult to get the box moving.Static friction is the force that is acting against the box.If you apply a light horizonta 200分求数学题 求过程A block of steel on a level, frozen pond, is given an initial speed V. Even though the block of steel issliding on smooth ice, there will be a small friction force that will slow the block of steel until itcomes to a stop. friction force on the rack Fr------------------wheel force on the rack在工程机械上是什么意思? love is a force of nature是什么意思 有图 求真相.Suppose the roller coaster in Fig.6-38 (h1 = 37 m,h2 = 12 m,h3 = 20) passes point A with a speed of 1.20 m/s.If the average force of friction is equal to one third of its weight,with what speed will it reach point The distance travel What kind of force is the force on the student by the backpack?A gravitational force.A nuclear force.An electromagnetic force.三个选项 选哪个? there is a barge amount of energy wasted due to friction是什么意思? love is a mysterious and a complicated force怎么翻译 There is a large amount of energy wasted due to friction译成中文什么意思嘛译