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GURUKUL CENTRAL ACADMY, CH. – 12. TIME AND MOTION, WORKSHEET-1, A. 1. time, oscillation 2. to and fro, periodic, 3. distance, divided 4. equal, equal, B. 1. True 2. True 3. False 4. False, 5. True 6. True 7. False 8. True, WORKSHEET-2, A. 1. Bodies A & B are moving in uniform motion., 2. Body A, 3. Body B, 4. Body A, , TEXTBOOK EXERCISES, Page 152 Try These, 1. False, 2. True, , 3. True, , 4. True, , 5. True, , EXERCISES, A. 1. d., 7. b., B. 1., , 2. b. 3. a., 8. c. 9. a., , Sundial, 5. increases, , 4. b. 5. c., 10. b., , 6. b., , 2. periodic 3. time period 4. odometer, 6. Speed 7.graph, 8. Straight
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GURUKUL CENTRAL ACADMY, C. 1. Time period, 4. Sample pendulum, , 2. One oscillation, 5. Speed, , 3. Sundial, 6. Motion, , C. 1., , False 2. True 3. False 4. False 5. False, 6. False 7. True 8. False, , D. 1., , Agree, 2. No, 3. Speed, 4. Periodic motion, 5. 10m/s 6. Straight line, 7. Non-uniform motion, , E. 1., , A body is said to be in motion if its position changes with time., 2. Any motion that repeats itself after a fixed interval of time is called, a periodic motion. The motion of simple pendulum is periodic., Example, simple pendulum and planetary motion., 3. A simple pendulum consists of a small metallic ball suspended, from a rigid support through a thread., 4. Distance travelled by an object in unit time is called speed., The SI unit of speed is metre per second (m/s)., 5. If time period of a pendulum is two seconds, it is called a seconds, pendulum., 6. Speedometer: The device which records the speed of a, vehicle directly in km/h is called speedometer, Odometer: The device that measures the distance moved by a, vehicle is called odometer., 7. 0.5 seconds, 8. S = D/T, 9. When a pendulum moves from its mean position to the extreme, position and them comes back to its mean position once, it is called, oscillation., 10. 10 m/s
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GURUKUL CENTRAL ACADMY, F., , 1. Sundial, sand clock and water clock., A sand clock or hourglass consists of two rounded glass bulbs, connected by a narrow neck of glass. It works on the principle that, all the sand from the upper glass bulb falls into the lower glass bulb, in a fixed period of time. This fixed period of time became the unit, in which time was measured. When the entire sand gets filled in the, lower bulb, the clock is inverted to allow the sand to fall again., However, measuring the hour of a day is not possible with an, hourglass., 2. Refer page 151., 3. Refer, , Activity 2, , 4. Uniform, , Motion:, 1. The motion of a body that covers equal distances in equal, intervals of time is called uniform motion., 2. Whenever a body is executing uniform motion, it is moving with, a constant (unchanging) speed., 3. Hands of a clock and heavenly bodies are in uniform motion., Non-uniform Motion:, 1. The motion of a body that covers unequal distances, , 2., , 3., , 5., , in equal intervals of time or vice versa is called non- uniform, motion., Whenever a body executes non-uniform motion, it moves with a, variable (changing) speed., Cars and scooters move in non-uniform motion, , i. The graph should be plotted using a sharp pencil and a ruler., ii. The scale of the graph should be taken appropriately according to, the minimum and maximum observation.
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GURUKUL CENTRAL ACADMY, 6. Refer, , fig. 12.11., , H. 1. 0.7 s, , 2. 8 m/s 3. 4166.67m 4. 3 h, , 5. 30 minutes, , I. 1. A, 2. Table B, 3. Graph A – Rabbit – 10 m; Graph B – Tortoise – 166.67 h
