Babita and Sheela class XII students were assigned a project based on magnetism.In their project work, they calculated the value of earth's magnetic field.When they submitted their project work for verification.
Mr.Raj, their physics teacher, corrected the mistake.Hew also suggested few books which could be of use to them.
What values did Mr.Raj exhibit towards his students? Mention any two.

Mr.Ramesh a physics teacher, was doing an experiment in lab using dry cell battery. The dry cell was weak, giving less voltage, which was not sufficient to give proper reading. One of the students asked, "Sir, can't we step-up the voltage using a transformer?" Teacher replied, "No, we cannot step up DC voltage using step up transformer and explained the reason and working of a transformer". The student then constructed a transformer for his physics project and studied the factors responsible for losses in a transformer.
1. What values are displayed by the student?
2. Why can transformer not be used to step-up DC voltage?

Ravi is using yellow light in a single slit diffraction experiment with slit width of 0.6mm. The teacher has replaces yellow light by x-rays. Now he is not able to observe the diffraction pattern. He feels sad. Again he teacher replaces x-rays by yellow light and the diffraction pattern appears again. The teacher now explains the facts about the diffraction and 
Which value is displayed by the teacher.
Give the necessary condition for the diffraction.

Arun lives in Delhi, His grandfather lives in a small village in Haryana.He always misses his grandfather, so he decided to purchase a mobile phone for his grandfather.He saved his pocket money and purchased the mobile phone.Now his grandfather communicates often with his family and now they are happy.
(a) What are the values Arun displayed in his act?
(b) Name the type of wave used in mobile communication.Write its frequency range.

Rita was studying in 10th class, one day she asked her father to explain the working of remote control of TV. Her father was not knowing the answer, but he made up his mind to understand the working of remote control. He found one shop where remote controls were repaired. The shopkeeper showed to Rita's father the inside of the remote control and explained her the working. Rita's father explained her the working of remote control, Rita was happy and satisfied.
(a) What are the values Rita's father displayed in his act?
(b) Name the diode used in remote control.