Ram is a student of class X in a village school. His uncle gifted him a bicycle with a dynomo ditted in it. He was very excited to get it. While cyciling during night, he could light the bulb and see the object on the teacher considered it an opportunity to explain the working to the whole class.

Ram is a student of class X in a village school. His uncle gifted him a bicycle with a dynomo fifted in it. He was very excited to get it. While cycling during night, he could light the bulb and see the objects on the road. He, however, did not know how this device works. He asked this questions to his teacher. The teacher considered it an opprtunity to explain the working to the whole class. Answer the following questions : (i) State the principle of working of dynamo. (ii) Write two values each displayed by Ram and his school teacher.

Bharat was doing an experiment by using an ammeter. Suddenly. it fell from his hand and broke. He was afraid. that he might be scolded and threaten by his teacher. His classmate advised him not to tell the teacher. but he refused and told his teacher. On listening lu him patiently, the teacher did not scold him and threaten as it was just an accident and used the opportunity to show the internal structure of the ammeter to the whole class. On the basis of above passage, answer the following questions: State the aim of anyone experiment, where Bharat could have used the ammeter.

Dinesh is a student of 10th standard. He went to a remote area of Rajasthan for trekking with his friends. Dinesh found that it was a sparsely inhabited area. He was surprised to know that there was still no electricity in this area. The children also had to study with kerosene lamps at night. The village farmers used diesel to run irrigation pumps. Actually, there were no power transmission lines which could bring electricity to this remote area. Dinesh was really disturbed by the living conditions of the people in this part of Rajasthan. One day Dinesh gathered all the people of village in the village school. He told them that if they put pressure on their area MLAs and MP for making available the required funds, then he could tell them about the devices to light up their homes and streets at night, play radio and television and also run irrigation pumps with electricity without there being power transmission lines. All the people agreed and Dinesh described them the devices to get electricity in their area in detail. The village people were very happy to know this and soon they got electricity in their area. (a) What was the device described by Dinesh to the village people to obtain electricity locally ? (b) What source of energy is made use of in this device to obtain electricity ? (c) Why do you think this device is more appropriate for an area like Rajasthan ? (d) What is the name of the single unit of this device ? What values are shown by Dinesh in this incident ?