work power and energy class 10

Question-1
(a) Define work and write its S.I unit.          [2 Mark]
(b) Define energy and establish relationship between S.I unit & commercial unit of energy.         [2 Mark]
(c)Two bodies A and B of masses 1 kg and 4 kg respectively have equal momentum find ratio of their K.E.        [2 Mark]

Question-2
(a) The work done by the heart for each beat is 1 joule. calculate the power of heart if it beats 72 times in a minute.          [3 Mark]
(b)The engine of train has yo apply a force of 5000 N to overcome friction to run at a uniform rate of 90 km/hr. What is the power developed by the engine?           [3 Mark]
(c)Differentiate between renewable and non-renewable form of energy resource.   [2 mark]

Section-B

Question-1 State the conditions in which force applied on a body does no work.         [2 Mark]
 (a) Derive formula of K.E.          [4 Mark]
(b) A 40 newton object is released from a height of 10 m. Just before it hits the ground. By which amount its kinetics energy decreased in joules.         [2 Mark]



(c) The kinetic energy of a body is 250J. Find work done to move a body of mass 20kg up-to a height of 5 m.        [4 Mark]
(d)  A 78-kg skydiver has a speed of 62 m/s at an altitude of 870 m above the ground.
i. Determine the kinetic energy possessed by the skydiver.
ii. Determine the potential energy possessed by the skydiver.
iii. Determine the total mechanical energy possessed by the skydiver.      [4 Mark]
Question-2
(a) Calculate the work done in lifting 100 kg of water through a vertical height of 5 m.   [2 Mark]
(c) What kind of energy transformation takes place when a body is dropped from a certain height?        [4 Mark]
Question-3
 (a) A jumper has a mass of 52 kg. She is moving with a speed of 2 m/s at a height of 54.6 meters above the ground. Determine the total mechanical energy of the jumper and work done to throw a shot put of weight 2.5 kg upto the height 20 m.         [4 Mark]
(b) Calculate the work done in lifting 200 kg of water through a vertical height of 6 m? [4 Mark]

Nomenclature of Hydrocarbons

                         ORGANIC CHEMISTRY                                                                           

Draw the complete structural formula and condensed molecular formula for each compound.

IUPAC Name	Complete Structural Formula	Condensed Formula
butane
2-methylhexane
3-ethyl-2-methylnonane
propene
4-methyl-2-heptene
ethyne
5,6-dimethyl-2-octyne
cyclopropane
1,3-diethylcyclohexane

Physics : chapter : Heat : grade 9

                                                                 Heat

1. Two bodies at different temperatures are placed in contact. State the direction in which
     heat will flow
2.  Define temperature and give its S.I units?
3.  Why does a piece of ice when touched with hand appears cold?
4. Name two substances which contract on heating
5.  Distinguish between Heat and Temperature
6. State three factors which affect the increase in length of rod on heating.
7. Loops are joined in metal pipes. Why?
8.  The unit calorie is related to _____________
9. The unit of coefficient of linear expansion is ______________
10. State the effect of temperature on the density of a substance.
11. What do you mean by anomalous expansion of water?
12.  What do understand by real and apparent expansion of a liquid.
13. Write a relation between Celsius and the Fahrenheit scales of temperature
14.  What do you understand by zero on kelvin scale. Write its value?

15. Express 100 degree Fahreinheit  in degree celsius and kelvin?

16. Express 100 K in degree celsius?

17. Name the liquid which is good conductor of heat

18.Name different modes of transfer of heat.

19. Name the material used for making the handles of cooking utensiles. Give reason for your answer.

20.Write some consequences of convection?

21. By the process of convection, heat always transferred vertically upwards. Give reason.

22. Why is a Ventilator provided in a room?

23. Write three differences between conduction, convection and radiation

Chemistry : Balancing the equations

Balance the equations

1.       H2 + O2 → H2O

2.       H2 + N2 → NH3

3.       Al2O3 → Al + O2

4.       KClO3 → KCl + O2

5.       S8 + O2 → SO2

6.       C2H6 + O2 → CO2 + H2O

7.       Al2(SO4)3 + Ca(OH)2 → Al(OH)3 + CaSO4

8.       P4 + O2 → P2O5

9.       Ag + S8 → Ag2S

10.       Al + Br2 → AlBr3