In a school, students are asked to save electricity both at school and home. They are told to switch off the lights and fans before leaving the class rooms. Two best friends Vijay and Ajay are in class 10th. Vijay saves electricity by switching the appliances off when not in use while Ajay makes fun of his habits. He always leaves the T.V. and computer ON. On the basis of above passage, answer the following questions: (a) Why is it necessary to save energy? (b) Which type of character is possessed by the friends?
Due to heavy winds a tree fell down in the middle of the road and the vehicles got stuck in the way. Two residents came forward to place it aside but could not accomplish it as they were too heavy. A passerby helped them with heavy blocks. They cleared the road and the traffic began to flow as usual. (i) Which value is shown by the passerby and the residents? (ii) Which energy is stored when the heavy log of the tree is lifted to some height?