1.

1. what is lubricant ? how does a lubricant reduce friction ?2. why is friction called a necessary evil? 3. what are the changes occur during adulescence ?4. A girl is 11 years old and 125cm tall . find her height at the end of the growth period using the formula ?​

Answer»

\huge\fbox\red {˙❥answer}

  1. Lubrication reduces the HEAT generated when two surfaces are in motion. It smoothes the process by forming a film between two surfaces that reduces friction and thus improves performance and efficiency. There are different variety of lubricants and oils available such as Engine Oil, Hydraulic Oil, and Greases.
  2. Frictional force causes a lot of losses in general upkeep and wear and tear of machinery. HENCE it is considered as a evil. But almost all crucial tasks cannot be CARRIED out without the presence of friction. ... Hence it is considered as a necessary evil .
  3. An adolescent may grow several inches in several months followed by a period of very slow growth, then have another growth spurt. Changes with puberty (SEXUAL maturation) may happen gradually or several signs may become visible at the same time.


Discussion

No Comment Found

Related InterviewSolutions