Class 10 Science

 

Time: 1:30 hrs                                                                                                    

Class: 10                                                                                                                                 FM: 40

Subject:  Science                                                                                                                  PM: 16

Group A (8x1 = 8)

1. Write short answer of the following questions .
a) What is the value of acceleration due to gravity 'g' at the centre of the earth?
b) Write any two example of bio-fuel.
c) Write the name of two machine based on Pascal’s law.
d) Write two examples of non-renewable source of energy.
e) What is upthrust?
f) What is free fall?
g) In which two factor does heat gain or loss by an object depend upon?
h) Write the relation between power of lens and its focal length.
Group B (6× 2 = 12)
2) An object weights 20 N in air and 16 N in liquid then answer the following questions .
i) What is the upthrust of the liquid on the object ?
ii) What is the weight of displaced liquid ? Write with reasons.
3) Write any two differences between Archimedes’ principle and law of floatation.
4) In context of Nepal , hydropower should be given more priority rather than fossil fuel . Why? Justify your answer.
5) Which thermometer is suitable to measure the temperature of mountain region? Write with reasons.
6) Write two causes of energy crisis.
7) When a man travels from hilly to terai region. What will happen to his weight? Explain your answer.
Group C ( 4×3 = 12)
8) Mass of Jupiter is 1.9 x 10²⁷ kg and mass of sun is 2× 10³⁰ kg. Calculate the distance between them if the gravitational force between them

is 4.166× 10²⁰ N

 

9) If three liquids A,B and C having equal masses are taken in three same size of beaker and exposed to sunlight . After 10 minutes the increased temperature in each is given in the table:

Liquid	Increased temperature
A	10°c
B	8°c
C	6°c

 

i)                    Which liquid has highest specific heat capacity? Why?

ii)                  If all the three liquids are heated to same temperature and put in the same beaker separately, which cool faster? Why?

10) Write the factors that affect heat energy. Calculate the amount of heat required to  increase the temperature of 2 kg water from 10°c to 20°C .( Specific heat capacity of water = 4200 J/kg°c)

11) Write any three ways to reduce energy crisis.

Group D.  (4×2 = 8)

12)Draw the ray diagram by placing the  object beyond 2F. Also  mention any two nature of the image thus formed . If the power of lens is +4D. Calculate the distance between lens and magazine to read properly.

13) What is heat equation?

Prove that Q = msdt.