Types of Friction
- Static Friction: This type of friction occurs when two objects are not moving relative to each other.
- Sliding Friction: Sliding friction happens when two objects are sliding past each other.
- Rolling Friction: This type of friction occurs when an object rolls over a surface.
- Fluid Friction: Fluid friction happens when an object moves through a fluid, such as air or water.
Factors Affecting Friction
Friction depends on the surface roughness and the force pressing the surfaces together. The rougher the surfaces and the heavier the load, the greater the frictional force.
Ways to Reduce Friction
- Using lubricants such as oil or grease.
- Smoothing or polishing the surfaces in contact.
- Using wheels or ball bearings to reduce contact area.
Real-life Examples
Friction is present in many everyday activities such as walking, riding a bike, or driving a car. It helps us grip things and prevents us from slipping. However, friction also causes wear and tear on surfaces and objects, so reducing friction is important in many industries and fields.
Study Guide
.◂Science Worksheets and Study Guides Third Grade. Relationships among living things
Study Guide
Relationships among living things 
Activity Lesson
Relationships Among Living Things Worksheet/Answer key
Relationships among living things Worksheet/Answer key
Relationships among living things Worksheet/Answer key
Relationships among living things Worksheet/Answer key
Relationships among living things Vocabulary/Answer key
Relationships among living things Vocabulary/Answer key
Relationships among living things
Activity LessonWorksheet/Answer keyWorksheet/Answer keyWorksheet/Answer keyWorksheet/Answer keyVocabulary/Answer keyVocabulary/Answer keyThe resources above cover the following skills:
LIFE SCIENCE
From Molecules to Organisms: Structures and Processes
Create representations to explain the unique and diverse life cycles of organisms other than humans (e.g., flowering plants, frogs, butterflies), including commonalities such as birth, growth, reproduction, and death.
Unity and Diversity
Construct an argument from evidence to explain the likelihood of an organism’s ability to survive when compared to the resources in a certain habitat (e.g., freshwater organisms survive well, less well, or not at all in saltwater; desert organisms survive well, less well, or not at all in woodlands).
Create models that illustrate how organisms and their habitats make up a system in which the parts depend on each other.