Is it possible that the frictional force is perpendicular to the direction of motion???

Probably not, because the motion of the object is affected by this direction, sometimes it may be a component force, and the friction force is generated to keep the object in its original state, so it must not be perpendicular, but sometimes it will be the same direction of motion. It doesn't have to be the other way around.

Possibly. For example, if a wooden board is pulled by a rope and moves in a circular motion on a rough plane, if the rope breaks suddenly, the frictional force of the wooden board in the radius direction is due to centrifugal force, and the movement direction of the wooden board at the moment of the rope break is the tangent direction of the circle, which is perpendicular to the radius direction.

Motion is relative, depending on which direction of motion is perpendicular to each other.

Friction is in the direction of the perpendicular pressure.

There are such examples:

For example, there is a vertical wooden board on the trolley, and the wooden board is in contact with a small wooden block, when the trolley accelerates along the horizontal movement with a certain acceleration, the wooden block may be relative to the plank stationary together along the horizontal acceleration movement, and the thrust and friction of the gravitational wooden board are affected by the friction force to offset the gravity, that is to say, the friction is in the vertical direction, and the direction of movement is in the horizontal direction. Vertical!

This question will not come out of the college entrance examination.

The frictional force f=kn, which is only possible in the presence of pressure n. There is pressure before there is friction.

f=ma, and the resultant force f is the direction of acceleration.

If the frictional force and the direction of motion are perpendicular, i.e. at least one other external force is exerted on the object, then the state of motion will inevitably change.

When doing the problem, any force perpendicular to the velocity is completely unconsidered. In time, similar to flat throwing and oblique throwing, the gravity is vertically downward, and the force analysis in the X and Y axis directions is also carried out and considered separately.

Don't think about it anymore.

Good luck!

After the spacecraft is launched, if a person walks in it, then the frictional force is perpendicular to the direction of the person's motion.

Hold the object to the right or left.

The case where the frictional force is the same as the direction of motion is:When friction is not an obstacle to motion, i.e., when friction is favorable to the motion of an object, then the direction of friction is the same as that of the object. For example, an object on a conveyor belt has the same friction as the object's movement.

For example, if we push a box, the direction of friction of the box is opposite to the direction of the box's movement; But the person pushing the box has the same direction of friction as the person (with the ground) and the person moving in the same direction.

Characteristic properties of friction:1.Friction is related to objects rubbing against each other, so the description of friction in physics is not generalized and not as precise as other forces.

Without friction, shoelaces cannot be fastened, and screws and nails cannot hold objects in place.

2.The biggest distinction within friction is between static friction and other frictional forces. Some people believe that static friction should not actually be counted as friction.

All other frictional forces are related to dissipation: it reduces the relative velocity of objects rubbing against each other and converts mechanical energy into heat.

The above content reference: Encyclopedia - Friction.

"Friction is always in the opposite direction of motion" is false, it should be that the direction of friction must be opposite to the direction of the relative motion of the object or the relative direction of the trend of motion. For example, if an object is moving in a circular motion on a disk, the frictional force experienced by it is perpendicular to the direction of motion, but the direction of friction is opposite to the direction of the relative motion trend of the object and the disk.

An object moving relative to a fluid is subjected to resistance. This resistance is in the opposite direction of its movement. In the case of laminar flow this resistance is proportional to its velocity, and in turbulent flow this drag force is proportional to the square of its velocity.

Sometimes an object is subjected to both drag and friction, such as a car that is in motion by both the resistance of the air and the rolling friction of its tires.

Although the direction of friction is always along the tangent of the contact surface, it may be in the same straight line as the direction of motion of the object, or it may be at any angle For example, holding a glass in your hand and moving it horizontally.

, because the glass itself has gravity, so it has a vertical downward movement tendency, and the glass is subject to a balanced force in the vertical direction, indicating that the direction of static friction given to the glass by the hand is vertically upward, and the direction of motion of the object is.

Horizontal, the two are perpendicular If the glass moves at a uniform speed in any other direction, and the direction of static friction given to it by the hand of the glass is always vertically upward, then the direction of static friction and the direction of motion of the object can be at any angle

For example, if you hold a bottle vertically with your hand and let the bottle move horizontally, the friction in the vertical direction will be perpendicular to the movement yard. When an object in a rising elevator moves horizontally, the static friction is perpendicular to the direction of the object's motion.

Place a small wooden block on a round wooden plate placed in a horizontal position. When the disc rotates, friction will be generated on the contact surface of the small wooden block and the disk, and the frictional force is the centripetal force that makes the small wooden block move in a circular circle, and its direction is directed to the center of the circle, and the direction of movement of the small wooden block is along the tangent key direction of the circumference, which is just perpendicular to the direction of the centripetal force.

This early source saying is wrong.

It is true that the direction of friction must be opposite to the direction of the relative motion of the object or the direction of the relative motion trend.

For example, if an object moves in a circular motion on a disk, the frictional force experienced by it is perpendicular to the direction of motion, but the direction of friction is opposite to the direction of the relative motion trend of the object and the disk.

Special attention is paid to the relative two words.

For example, an object placed on an inclined plane. There is friction between the object and the inclined plane, and the object is not subjected to other external forces.

When the object is at rest, the object has a downward tendency relative to the inclined surface, and the frictional force experienced by the object is upward.

When the object slides downward, the object moves downward with respect to the inclined side, then the object experiences an upward frictional force.

When an object slides upward, the object moves upwards with respect to the inclined side, and the object experiences a downward frictional force.

No, friction is not perpendicular to the direction of motion.

The direction of friction is always opposite to the direction of relative motion or relative trend of motion, and can be at any angle to the direction of motion of the object.

Yes, the direction of frictional force is usually opposite to the relative direction of motion of the object. There are two types of friction: static friction and kinetic friction.

In the case of rest, the static friction between the two objects acts on the object at the point of contact, preventing the object from starting to move. The direction of the static friction force is opposite to the object that is about to start moving.

When the object starts moving, the static friction force changes to the kinetic friction force, and its direction is always opposite to the direction of the relative motion of the object. For example, when you push a chest with your hand, the box starts to roll forward with a band of friction in the direction of backwards, in the opposite direction of the box's forward motion.

In general, friction is the result of contact between objects, and its direction is usually opposite to the relative direction of motion of the object, but it can also change direction as the direction of motion of the object changes.

The force that hinders the relative motion (or relative tendency of motion) of an object is called friction. The direction of friction is opposite to the direction of the relative motion of the object (or relative to the tendency of the moving motion). There are three types of friction: static friction, rolling friction, and sliding friction.

When an object slides on the surface of another object, friction occurs between the contact surfaces that hinders their relative motion, which is called sliding friction. The magnitude of sliding friction is related to the magnitude of the roughness of the contact surface and the magnitude of the pressure. The greater the pressure, the rougher the contact surface of the object, and the greater the sliding friction generated.

The methods of increasing the favorable friction are: increasing the pressure, increasing the roughness of the contact surface, and the magnitude of the pressure. Ways to reduce harmful friction are:

Reduce the pressure, make the object and the contact surface smooth, separate the object from the contact surface, change the slide to roll, etc. <>

The frictional force does not have to be in the opposite direction of motion. It may be in the opposite direction to the movement of the object or the trend of movement, or it may be the same as the direction of the movement or trend of movement of the object.

Judgment method: 1. The condition for generating static friction is that there is a relative sliding tendency between objects, and the direction of static friction is opposite to the relative sliding trend between objects. Therefore, in order to determine the direction of static friction, it is necessary to determine the direction of the tendency of the relative sliding between objects.

The so-called hypothetical method is to assume that the contact surface is smooth, and determine the relative sliding direction of the two objects by assuming that the liquid penetrates, so as to determine the direction of static friction.

2. The relative sliding trend between some objects is not obvious, and it is not easy to judge the direction of static friction by the hypothetical method, but if the object is in equilibrium, the object equilibrium condition can be used to judge whether the object is subject to static friction and its direction.

3. The direction of some static friction is closely related to the moving liquid guess state of the object, so the direction of the friction force on the object can only be judged by the motion state of the object. <>