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Why the direction of normal reaction is perpendicular to the surface where friction is acting?
Daisyliza
This is because fluid pressure always acts in a direction such that the solid in it(whether submerged or not) goes out of the fliud.If the fliud is accelerating horizontally the fluid would want no disruption in its flow and hence take the solid in it in a perpendicular direction(ie the direction of the acceleration).
Wiki User
∙ 14y ago
Wiki User
∙ 12y agoIt doesn't have to be, it just has to be the opposite of gravity. Similarly, friction must be the opposite of the direction of motion, and because most of the mechanics problems that the average person encounters are hypothetical idealised situations, they are perpendicular.
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Is the reaction force on a surface always perpendicular to the surface?
yes i presume
Is it true that weight affects the amount of friction between the object and a surface?
Yes. Weight, being a force perpendicular to the surface, affects the magnitude of the friction, but not the friction coefficient.
Does the surface area of an object affect the amount of friction between the object and the surface?
No, it doesn't, the only important thing is the force perpendicular to the surface (weight) and friction coefficient.
How does mass affect the friction of an object?
According to the laws of mechanics. Friction is defined as the force resisting motion. Whenever there is motion there is friction opposing it. The frictional resistance of a surface is given by an unit less index called coefficient of friction. This depends upon the roughness of the surface. Friction = coefficient * normal reaction Thus, from the formula it is seen that friction is directly proportional to normal reaction and coefficient of friction. Normal reaction is nothing but the the perpendicular reaction provided to a body by a surface as a result of all the perpendicular forces acting on the surface due to the body. for example, consider a block of wood on a table. Weight of the body acts downwards perpendicular to the surface of the table.Thus here the table will apply an equal and opposite force on the block(Newton's third law). This force will be perpendicular to the both the block and the table surface.Thus it is known as the normal reaction. As is seen that every object exerts it weight upon the surface it is placed on. Weight = mass* g. Where g = acceleration due to gravity(=9.81 for earth surface) Thus increase in mass increases normal reaction. Hence increasing friction. "FRICTION VARIES DIRECTLY WITH MASS"
What is the relationship of the starting friction to the static friction between two objects?
When an object is at rest on a particular surface, the frictional force keeping it from sliding in any given direction is known as static friction; the magnitude of this force is always less than or equal to the product of those surfaces' static friction coefficient and the component of the gravitational force (weight) of the object perpendicular to the plane of the surface, the latter of which is equal to the normal force that is exerted by the intermolecular bonds in the surface material, upward and perpendicular to the plane of the surface itself. (In other words, Fs ≤ µsFn, where Fs=force of static friction, µs=static friction coefficient, Fn=normal force of surface upon object.)
What describes the motion of the media for a surface wave?
The motion is parallel to wave direction The motion is both parallel and perpendicular to wave direction. The motion is perpendicular to wave direction.
What does friction mean in science?
Friction is a force that is created when an object or surface moves over another object or surface making the object to resist the direction of motion ( accelerate in the opposite direction).
Why a vertical datum is alevel surface not a horizontal surface?
because the datum surface is perpendicular tothe direction of gravity at any point on it.but the horizontal surface is perpendicular to vertical at one point on it :D
What factors affect the force of friction between sufaces?
The frictional force is described by F = μR where μ is the coefficient of friction (the roughness of the surface) and R is the force the object exerts perpendicular to the surface.
Name 3 common ways you may use to reduce friction?
Reduce contact surface in the direction of friction. Introduce lubrication. Reduce load acting upon the friction surface.
How friction affects motion?
Friction is a very helpful thing and with out it you couldn't move, speed up, slow down, change direction, bend, or twist. Without friction nothing would ever happen. Friction can oppose motion or it can make it difficult for an object to move across a surface. Friction both helps an hinders every thing we do.the object would not move without frictionThe friction acts in the opposite direction to that of direction of motion.So friction slows the object and if no external force is applied the object will come to stop.Friction is a force that opposes the direction of motion between two materials. It is parallel to the surface your object is touching. Friction depends on the coefficient of friction and the normal force (force exerted perpendicular to the surface your object is on; opposes gravity on a flat surface). There are two kinds of friction: static and kinetic. Static friction must be overcome in order to move an object. Once the object is in motion the friction acting on it is called kinetic. Static friction has a threshold of force that is needed to get the object moving but once the object is in motion it can be moved at a constant velocity with less force required.
Investigate-how friction increases with increase of size of an object?
The force of friction on an object is equal to the coefficient of friction times the force perpendicular to the surface (normal force). When the mass of an object increases, the normal force increases, and the force of friction also increases. However, because the equation does not involve surface area, increasing surface area has no affect on the force of friction.
