Friction is the ____ present between two surfaces of two objects when these ____ against one another. ____ opposes the motion of objects. The Rougher the surface, the ____ the friction. Friction is present between your shoes and the ground when you ____ As you try to step forward, you push your foot ____ Friction holds your shoe to the ____ , allowing you to walk. You would not be able to walk without friction, It is difficult to walk on slippery ice, where there is ____ friction. Writing with a pencil requires friction . You could not hold a pencil in your ____ without friction. It would slip out when you tried to hold it to ____ . The graphite ____ lead would not make a mark on the paper without friction. A pencil eraser uses friction to ____ off mistakes written in pencil lead. Rubbing wears out the eraser due to ____ , while the ____ worn off gather up the pencil lead from the paper . Your car would not start moving if it wasn't for the friction of the ____ against the street. With no ____ , the tires would just spin. Likewise, you could not ____ without the friction of the brakes and tires. Therefore an ____ road is dangerous. The same applies to when there are oil spills on the road. When you want to slide a heavy box across the floor, you would want to reduce the friction between the box and the ____ so that it would be easy to move. Lubrication is often a way to reduce ____ . This can be done by polishing the floor. There are also sliders or rollers that can be used to ____ the friction. Other examples where friction is not ____ is when you would like to go down a ____ while in the playground. Friction produces heat. When two objects are rubbed together, friction is produced which then produces ____ When you rub your hands together they get ____ because of ____ . Also, this is why when rubbing two sticks together will eventually produce a ____ . Friction can be ____ or non-useful. It is necessary in instances to prevent ____ or sliding. However it can be a problem as it will ____ down motion.

Friction

打印
嵌入

排行榜

视觉风格

选项

切换模板

恢复自动保存：？