# Gravitational force and frictional force

8 de Jul de 2020
1 de 19

### Gravitational force and frictional force

• 1. Presented By Sadam Hussain Roll No: F16TEO5 Assigned By: Sir Shamshad Ali Topics: Gravitational Force and Frictional force Department: Textile Engineering
• 2. A push or a pull on an object in a particular direction. What is a Force ?
• 3.  Does not require contact: NON-CONTACT FORCES Force through CONTACT Virtually all actions require a… Magnetic Gravity: Forces are measured in NEWTONS
• 4. An attractive force that exists between all objects that have mass. This force is dependent on mass and distance from the object. Gravity
• 6. • Gravitation is an Natural Phenomenon by physical bodies attract to each other. • Newton focused on his attention on the motion of the moon about the earth. • He declared that the laws of nature that operating between earth and the apple is same as the laws operating between earth and moon. • He calculated the acceleration due to gravitation (on earth) to be 9.8m/s2 . • Newton predicted that a ∝ 1 𝑟2
• 7. • Also, • F ∝ 𝑚 𝑟2 • By , The third law of motion, the force on a body due to the earth must be equal to the force on the earth due to the body. Therefore, this force should also be proportional to the mass of the earth. Thus , the Force between the earth and a body is • F ∝ 𝑀𝑚 𝑟2 • F= 𝐺𝑀𝑚 𝑟2 • G is called the universal constant of gravitation and its value is found to be 6.67x10-11 N-m2 /kg2 .
• 8.  The rotation of the earth around the sun or that of the moon around earth is explained on the basis of this law.  The tide are formed in ocean due to the gravitational force of attraction between earth and the moon.  The value of g can be used to predict the orbits and time period of an satellite. Attraction Force between two bodies
• 10. Friction is the force that resists the movement of a surface over another surface during sliding. When the textile materials are processed, then friction is developed between the fibers. The properties which are shown by a textile material during friction is known as frictional property. This properties are shown during processing. Too high friction and too low friction is not good for yarn. Therefore it is an important property when yarn manufacturing and processing. Introduction
• 12. The force that must be overcome in order to start sliding is called static friction. The force that resists continued sliding is known as kinetic friction. There are two types of friction Static Friction Kinetic Friction
• 13. The behavior of fiber during drafting. The frictional force holds together the fiber in yarn, i.e, frictional force helps to spun the fiber to yarn. In Fiber Stage
• 14. • If the frictional force is too low, yarn strength will be low. • Friction increases the luster and smoothness of yarn. • Friction makes more clean yarn. • Friction increases hairiness. • Friction occurs nep formation In Yarn Stage
• 16. • Fabric feelings varied for difference between static and kinetic friction. • Fabric will be slippery if µs >µk is high. Fabric will be harsh if µs >µk is low. Here, µs= Co- efficient of static friction, µk= Co-efficient of kinetic friction. • If the frictional force is high the handle properties of fabric quality will be low. • High static friction causes high breakage of yarn in weaving. In Fabric Stage
• 18. 1.Friction holds the fibre in a sliver and hence material does not break due to self weight. 2.Friction helps in drafting and drawing process. 3.Uniform tension can be maintained in winding and warping because of friction. 4.Friction helps in twisting during spinning. 5.Friction modifies the luster and appearance of a cloth. 6.Friction makes more clean yarn.