G8-PHY-L2 Friction

What is friction?

• A force that attracts objects to each other
• A force that opposes the motion of objects
• A force that pushes objects apart
• A force that causes objects to spin

What causes friction?

• Smooth surfaces
• Rough surfaces
• No surfaces
• Friction is not caused by surfaces

What happens to friction if the two surfaces are pressed harder?

• Friction increases
• Friction decreases
• Friction stays the same
• Friction disappears

What is the force required to overcome friction when an object starts moving?

• Static friction
• Sliding friction
• Rolling friction
• Fluid friction

What is the force required to keep an object moving with the same speed?

• Static friction
• Sliding friction
• Rolling friction
• Fluid friction

Why is friction important in our daily lives?

• It helps us move objects easily
• It helps us hold objects firmly
• It helps us generate heat
• All of the above

How can friction be increased?

• By making surfaces smooth
• By reducing the force applied
• By using lubricants
• By making surfaces rough

Why are the soles of shoes and the tires of vehicles treaded?

• To reduce friction
• To increase friction
• To eliminate friction
• To make them look stylish

What is the resistance to the motion of an object called when it rolls over another body?

• Static friction
• Sliding friction
• Rolling friction
• Fluid friction

What is the common name for gases and liquids?

• Fluids
• Solids
• Particles
• Substances