Welcome To Our Presentation

Mokhlesur Rahman

18-158

SN. NAME ROLL REMARK

1 Enamul Huque 18-054

2 Raihanul Islam 18-056

3 Md. Sazzad Hossain 18-068

4 Emon Hasan Rahat 18-134

5 Mokhlesur Rahman 18-158

6 Mst. Nasrin Sultana 18-206

Group NO: 12

Friction

Our Presentation Our Presentation on:on:

• Friction Basics

• Measuring Friction

• Friction and Gases

• Friction and Liquids

• Friction: Static vs. Kinetic

Md. Sazzad Hossain

18-068

Friction BasicsFriction Basics• Friction is the "evil" of

all motion. Friction is a Force that holds back the movement of a sliding object.

• Move something left, friction pulls right. Move something up, friction pulls down.

Friction BasicsFriction Basics• It appears as if nature has given us

friction to stop us from moving anything.

Emon Hasan Rahat

18-134

Measuring FrictionMeasuring Friction

• Measures of friction are based on the type of materials that are in contact. Concrete on concrete has a very high coefficient of friction.

• That coefficient is a measure of how easily one object moves in relationship to another.

Measuring Friction Measuring Friction

Scientists have discovered

that there is even less friction in your joints than in Teflon! It is one more example at how efficient living organisms can be.

Raihanul Islam

18-056

Friction and GasesFriction and Gases

• Friction only happens with solid objects, but you do get resistance to motion in both liquids and gases. This doesn't involve sliding surfaces like friction does, but is instead the kind of resistance you get if you try to push your way through a crowd.

Friction and GasesFriction and Gases

• It's a colliding situation, not a sliding one. If the gas is air, this is referred to as air resistance.

Mst. Nasrin Sultana

18-206

Friction and Liquids

• Although liquids offer resistance to objects moving through them, they also smooth surfaces and reduce friction. Liquids tend to get thinner (less viscous) as they are heated.

Friction and Liquids

• Car engines have a lot of moving parts, and they rub on each other. The rubbing produces friction and the result is heat. When oil is added to a car engine, the oil sticks to surfaces, and helps to decrease the amount of friction and wear on the parts of the engine.

Enamul Huque

18-054

Friction: Static vs. Friction: Static vs. KineticKinetic

Static :If you try to slide two objects past each other, a small amount of force will result in no motion. The force of friction is greater than the applied force. This is static friction.

Kinetic : If you apply a little more force, the

object "breaks free" and slides, although you still need to apply force to keep the object sliding. This is kinetic friction.

Thank youThank you