Friction can be defined as a type of force that prevents two smooth surfaces from sliding together on each other. Friction is a strong force that oposses motion when two surfaces come in contact with each other.
The different methods/ways to reduce friction include;
- Application of lubricant to surfaces
- Streamlined bodies; this goes a long way in preventing friction between two bodies.
- Decrease in weight; reducing the amount of weight on a substance can also help to reduce friction
- Applying wheels to objects that move/roll on the ground.
What you want.. you would need to post your question
Number a is a correct one
The correct answers are:
B. plant growth;
C. animal actions;
The mechanical weathering is a type of weathering where physical force is included into the breaking up of the rocks. The plants and the animals are both causing this type of weathering with their actions. The plants can cause mechanical weathering with their roots, as they grow and surround a rock, they are able to create such a pressure that they can break the rock apart. Also, as their trunks are getting bigger, if there's rocks right next to them, the pressure from the growing of the trunk will crack the rocks. The animals are able to move the rocks, as well as pushing them, or even deliberately throwing them, so they manage to break up parts of them and cause mechanical weathering.