SCIENCE AND TECHNOLOGY (212)

Transcription

1 SCIENCE AND TECHNOLOGY (212) TUTOR MARKED ASSIGNMENT Note: Max. Marks : 20 All questions are compulsory. The marks allowed for each question are given against it. Write your name, enrolment number, AI name and subject on the top of the first page of the answer sheet. When a piece of paper and a coin are dropped from the same height simultaneously. The coin reaches the ground first and paper takes some times in reaching to the ground. It we crumple up the piece of paper in the form of a ball and let the two drop from the same height again they reach the ground almost at the same time. Explain the science behind this activity. 0 0 C 100g 50 0 C (See Lesson-11) 4.2 J Cal 1 80 Cal/g 1 Cal g 1 / 0 C 1 100g ice at 0 0 C is uniformaly heated to convert it into water at 50 0 C. Calculate the amount of heat taken by ice and water in joules. 17

2 Given: Latent heat of fusion of ice = 80 Calorie / g Specific thermal capacity of water = 1 Calorie g 1 0 C 1 1 Calorie = 4.2 J/Cal. (See Lesson-14) Explain the following reactions with example. Combination reaction. Double displacement reaction (See Lesson-4) Balance the following reactions. (See Lesson-4) After cutting the wheat crop and beginning to rice crop, farmers row a Leguminous crop such as dal or lentil or pea in between. Why? Explain 3-4 sentences. (See Lesson-31) Name the type of cell division in which four daughter cells are formed from one mother cell in the and state two points of difference between this cell division and the other kind in which one parent cell gives rise to two daughter cells. (See Lesson-21) Answer any one of out of the following questions in about 100 to 150 words. 18

3 N A A coil of N turns of insulated copper wire is closely wound over a cardboard pipe. The free ends of the coil wire are connected to a battery, a rheostat and an open key as shown. A is a point on the axis of the coil. Answer the following questions with reason: A K K C X Y' A Which direction will a magnetic needle stay when placed at A. What will happen when key K is closed? Keeping K closed when moving contact C of the rheostat is moved from X to Y' what will happen. If a pivoted needle of iron were placed at A, how will the answers to and change. (See Lesson-17) Explain the difference between the following. Microphone and Loudspeaker Pitch and timbre 19

4 Radar and Sonar Electromagnetic waves and mechanical waves (See Lesson-18) Answer any one of out of the following questions in about 100 to 150 words. In the picture given above identify and name any two abiotic and biotic components of the ecosystem. Also define abiotic and biotic components of the environment. (See Lesson-29) The level of biodiversity is species biodiversity, which are the other two? Why is it necessary to classify biodiversity? Give two reasons. What are the bases on which the living beings are classified into five kingdoms of life. (See Lesson-19) Prepare any one Project given below: (v) 20

5 (c) (d) (e) Visit in your area and collect the following articles. Copper wire, Sulphur, Aluminium sheet, Iron nail, (v) Iodine crystal Answer the following: Classify them into metals and nonmetals Iron nail has a brown layer why is it so? (c) Which one is a better conductor of heat? (d) Write down the reaction of metals with water. (e) Write down the reactions of nonmetals with water. (See Lesson-27) (v) Identify an ecosystem in your neighourhood which may be a pond, a river, a garden, an agricultural field, a forest, a park or even an aquarium in your friends house present to your tutor an account of the same in the form of a power point presentation or a scrap book or an illustrated report with photographs / pictures (from books / journals / internet etc.) and relevant tables. You need to include: Name of the place / city. Kind of ecosystem - natural, humannade. Specific characterstics of components. Details of components. (v) Comments on impact on human activities if any. (See Lesson-29) 21