Question

ANSWER THE FOLLOWING: 1. What is the principle of measurement? Elucidate your answer with proper example. Explain the term: “Specific gravity of iron 7.5”. (3) 2. Why do we need distilled water for all the experiments involving RD bottle? What would happen to the specific gravity of iron if I use salt water. Explain your answer. (3) 3. What is a lactometer? Kindly state the principle of its working. 4. In the following situation where the α of brass is 17 and copper is 19, can these two be used to construct a fire alarm. Justify your answer. Rishi wrote that β of ethanoic acid is 17. Is he correct? Justify your answer. Rishi is trying to dry his clothes on a rainy day. Suggest him the perfect method to do so. (3) 5. A feather is dropped on the moon from a height of 2.52 meters. The acceleration of gravity on the moon is 1.67 m/s2 . Determine the time for the feather to fall to the surface of the moon. Find the final velocity by which it hits the ground. Knowing the strength of Jasprit Bumrah, he throws a ball upwards on moon with a speed of 1800cm/min. Calculate the maximum height the ball will attain. (3) 6. A kangaroo is capable of jumping to a height of 2.98 m. Determine the takeoff speed of the kangaroo. What should be his takeoff speed If he wishes to attain the same height on a planet with gravity of 4.5 m/s2. (2) 7. A hot object loses heat to its surroundings in the form of heat radiation. The rate of loss of heat depends on the : (1) • temperature of the object • temperature of the surroundings • temperature difference between the object and its surroundings • average temperature of the object and its surroundings 8. Which one of the following is the mode of heat transfer in which warm material is transported so as to displace a cooler material? (1) • Conduction only • Convection only • Radiation • Both conduction and convection 9. Why in solids we do not see the process of convection and in fluids we do not see the process of conduction? Explain your answers on the basis of Kinetic theory of matter. (2) 10. A bullet leaves a rifle with a muzzle velocity of 521 m/s. While accelerating through the barrel of the rifle, the bullet moves a distance of 0.854 m. Determine the acceleration of the bullet (assume a uniform acceleration). ( 2) 11. What would happen to a hole in a metal sheet when the sheet is heated? (1) • It decreases in size • It increases in size • No change is seen • First increases and then decreases 12. With proper diagram explain the working, and principle of a fire alarm. Also justify which materials are used for what purpose (5)

Answer 1

Answer:

Elucidate your answer with proper example. ... Explain the term: “Specific gravity of iron 7.5”. (3) 2. Why do we need distilled water for all the experiments involving RD ...