Chapter-12 Friction

Explanation:

The frictional force is acting in the opposite direction of the book's motion, so it is acting in the opposite direction to the tilt of the desk, which would be upwards.

Explanation:

It would make it more difficult to walk on the floor because the soap reduces the friction between the sole of your shoes and the floor, making it slippery and increasing the likelihood of slipping or falling.

Explanation:

Sportsmen use shoes with spikes to increase traction and grip on the playing surface, which helps to prevent slipping and allows for better acceleration, stability, and overall performance.

Explanation:

Seema will have to apply a larger force because the heavier box has more mass and therefore more inertia, requiring a greater force to overcome its resistance and move it across the same floor.

Explanation:

Sliding friction is less than static friction because the force required to start an object moving from a resting position is greater than the force required to keep it moving at a constant speed.

Explanation:

Friction is a friend when it prevents objects from slipping, such as car tires on the road. Friction is a foe when it causes wear and tear, such as in engine parts.

Explanation:

Objects moving in fluids must have special shapes to reduce drag and increase efficiency. This is achieved by reducing turbulence and pressure differences around the object's surface.

Explanation:

Sliding friction is the resistance force that opposes the motion of an object when it slides over a surface. It is caused by the irregularities in the surfaces that are in contact and the interlocking of the surfaces at the microscopic level.

Explanation:

Static friction comes into play when an object is at rest and an external force is applied to it. The force of static friction acts in the opposite direction of the applied force until the object begins to move.

Explanation:

Lubricants are substances that are applied between two surfaces in motion to reduce friction and wear. They act as a barrier and provide a smooth surface for the moving parts.

Explanation:

Rolling friction is the force that opposes the motion of a rolling object. It is caused by the deformation of the object and the surface it is rolling on, and is generally much lower than sliding friction.

Explanation:

Fluids are substances that can flow and take the shape of their container. They can be either liquids or gases and are characterized by their ability to exert pressure and resistance to deformation.

Explanation:

Yes, fluids can exert frictional forces on objects moving through them, known as fluid friction or drag. This resistance to motion is caused by the viscosity and turbulence of the fluid.

Explanation:

Air resistance, also known as drag, is the force that opposes the motion of an object through the air. It is caused by the friction and pressure differences between the air and the object's surface.

Explanation:

Drag, also known as fluid resistance, is the force that opposes the motion of an object through a fluid. It is caused by friction and pressure differences between the fluid and the object's surface.

Explanation:

Friction is a contact force, meaning that it occurs when two surfaces are in contact with each other. The force of friction acts in the opposite direction to the applied force.

Explanation:

It is difficult to walk on ice because the ice surface is very smooth, reducing the friction between the shoe and the ice. This results in less grip and stability, making it harder to maintain balance.

Explanation:

Yes, the water offers a force of friction called drag or fluid resistance to the boat's movement. This resistance depends on the speed of the boat, the shape of its hull, and the properties of the water.

Explanation:

Friction increases when two surfaces are pressed together because the contact area between them increases, resulting in more interlocking and deformation of the surfaces. This leads to a greater force of friction resisting motion.

Explanation:

Friction is the force that resists motion between two surfaces that are in contact with each other. When an object is in motion, friction acts in the opposite direction to the object's motion, slowing it down and eventually bringing it to a stop. This is known as kinetic friction.

Explanation:

There are many types of oils used as lubricants, such as mineral oil, synthetic oil, and vegetable oil. Oil lubricants are used in various applications, including automotive engines, machinery, and industrial equipment. Grease is a semi-solid lubricant that consists of oil and a thickener, such as soap or clay.

Explanation:

Smoother surfaces produce less friction than rough surfaces. This is because the microscopic irregularities and bumps on a rough surface create more points of contact with another surface, increasing the friction between them.

Explanation:

Due to a combination of factors, including friction, pressure, and the materials used to make the sole. When we walk, run, or stand, our body weight puts pressure on the soles of our shoes, causing them to compress and flatten out. This can cause the materials to break down over time, which leads to the gradual wearing away of the sole.

Explanation:

It depends on several factors such as the material of the surface and the force pushing against it. In general, rougher surfaces tend to produce more friction than smooth surfaces.

Explanation:

When two metal surfaces come into contact and rub against each other, they create friction, which can cause damage to the parts and increase energy consumption. Ball bearings help to reduce this friction by separating the moving parts with small steel balls, which roll between them instead of rubbing against each other.

Explanation:

It is due to the materials used and their design. The steps of foot over-bridges are made of durable materials such as reinforced concrete or steel, which are known for their strength and durability. These materials can withstand heavy foot traffic and the weight of people and their luggage without wearing out quickly.

Explanation:

To reduce friction and increase the speed and smoothness of the playing surface. The board surface is usually made of wood, which can create friction when the carrom men and striker slide over it. This friction can slow down the carrom men and reduce the accuracy and speed of shots.

Explanation:

The direction of force of friction is opposite to the direction of motion or attempted motion between two surfaces that are in contact with each other. The direction of force of friction can also vary depending on the angle of the surface or the force being applied.

Explanation:

Friction is the force that opposes motion between two surfaces that are in contact with each other. When two objects are in contact, the surface irregularities of the objects interlock with each other, creating resistance to the motion of one object relative to the other. This resistance is what we call friction.

Explanation:

Static friction comes into play when two surfaces are in contact with each other but are not moving relative to each other. Static friction is the force that prevents an object from moving when a force is applied to it.

Explanation:

To increase the friction between their hands and the surface of the court, which can improve their grip and prevent slipping. The game is usually played on a court made of a hard, smooth surface like concrete or wood, which can become slippery if it gets wet or if players sweat.

Explanation:

To reduce air resistance or drag, which helps them move through the air or water more efficiently and with less energy, allowing them to travel faster and farther.

Explanation:

To improve traction and grip on the road surface, especially in wet or slippery conditions. Tires without treads would have a larger surface area in contact with the road, creating more friction and resistance, which can lead to higher fuel consumption and more wear and tear on the tires.

Explanation:

When the rubber sucker is pressed against a smooth, non-porous surface, such as glass or tile, it seals against the surface and pushes out the air between the sucker and the surface. As a result, the air pressure inside the sucker is lower than the atmospheric pressure outside the sucker, creating a partial vacuum.

Explanation:

It means that force is always a result of an interaction between two or more objects. Whenever two objects interact with each other, they exert equal and opposite forces on each other, according to Newton's third law of motion.