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Multiple Choice

Which of the following statements about the direction of friction is correct?

• Friction always acts in the direction of motion

• Friction always acts opposite to the direction of relative motion or tendency

• Friction acts perpendicular to the surface

• Friction acts randomly

Multiple Choice

According to the definition, what are the three necessary conditions for friction to occur between two objects?

• Objects must be in contact and pressed together, the contact surface must be rough, and there must be relative motion or tendency of motion

• Objects must be in contact and pressed together, the contact surface must be smooth, and there must be relative motion

• Objects must be in contact, the contact surface must be rough, and there must be no relative motion

• Objects must be in contact, the contact surface must be smooth, and there must be no relative motion

Open Ended

Explain how friction can be both beneficial and detrimental in everyday life, using examples from the images.

Open Ended

Describe the difference between direct contact and non-contact situations in terms of friction, based on the images.

Multiple Select

Select all situations where friction is present.

• A book lying on a table without moving

• A person walking on the ground

• A block suspended in mid-air

• A car tire rolling on the road

Multiple Choice

How does increasing the pressure affect the frictional force according to the experiment described?

• It decreases the frictional force

• It does not change the frictional force

• It increases the frictional force

• It eliminates the frictional force

Open Ended

Based on the examples provided, explain how surface roughness influences friction in daily life and industry.

Open Ended

Describe a real-life situation where static friction is important for safety.

Multiple Choice

When pushing a box across different surfaces, which surface would likely result in the least sliding friction?

• Carpet

• Ice

• Sandpaper

• Concrete

Multiple Select

Which of the following are factors that affect sliding friction?

• Pressure between surfaces

• Surface roughness

• Temperature

• Type of material

Multiple Choice

Which of the following best describes the main difference between rolling friction and sliding friction, as explained in the first image?

• Rolling friction is much smaller than sliding friction.

• Rolling friction is much larger than sliding friction.

• Rolling friction and sliding friction are equal.

• Rolling friction only occurs in liquids.

Open Ended

Based on the first and fourth images, which factors influence friction and how can friction be beneficial in daily life?

Open Ended

Explain how friction is utilized in the design of sports shoe soles and car tires, based on the information provided in the third and fourth images.

Multiple Choice

Which of the following is NOT a factor that affects friction?

• Surface roughness

• Weight of the object

• Color of the object

• Type of material

Open Ended

After learning about friction, what is one real-life situation where understanding friction could help you solve a problem?