What are the important questions in Science of DLE?
Answers
How are work and energy interrelated? Write with suitable example. (2)
a. If the wooden block has a mass of 2 kg and is raised by Ram up to a height of 1.5 m, what work will be done? [g = 9.8 m/s]. If it takes time of 0.25 minute, calculate the power of Ram, in horse power. (2+1=3)
Complete the following word equations: (2)
Hydrogen + Oxygen ® …………………..
Nitrogen + …………… ® Ammonia
a. Define molecule. Draw the diagram of molecular structure of following compounds that you have made in science lab-work by the help of molymode model. (1+1+1=3)
Methane ii. Water
Write one difference between protons and electrons on the basis of their mass. Calculate the molecular weight of chlorine molecule (Cl2). (1+1=2)
What is atmospheric pressure? Write its cause. What is its value at sea level? (1+0.5+0.5=2)
Perform an activity to prove atmosphere exerts pressure with procedure, observation, necessary diagrams and conclusion. (3)
a. What is 1 Pascal pressure? Prove liquid pressure P = dgh, where symbols have their usual meaning. (1+2=3)
If 5 cm3 of wood weighs 40 gm and same volume of water weighs 50 gm. What is the relative density of wood? (2)
a. What do you mean by the statement ‘a heater is of power 760 watt’? Write the devices that transform following forms of energy. (1.5+1.5=3)
Mechanical to electrical
Light to electrical
Potential to kinetic and then to electrical