Karnatak University 2007 Science - Question Paper

(B) Beta rays are emitted
(C) Alpha and Beta rays are emitted simultaneously
(D) There may be Gamma rays along with Alpha or Beta rays.
Ans :
22. The accurate formula which shows nuclear fission of Uranium–235 is
(A) 92 U 235
——? 56 Ba 141
+ 36 Kr 92
+ 3
0 n 1
+ energy
(B) 92 U 235 + 0 n 1
——? 56 Ba 41
+ 36 Kr 92
+ 3
0 n 1
+ energy
(C) 92 U 235 + 0 n 1
——? 56 Ba 140
+ 36 Kr 92
+ three 0 n 1
+ energy
(D) 92 U 235 + 0 n 1
——? 56 Ba 141
+ 36 Kr 92
+ three 0 n 1
+ energy.
Ans :
23. one mg of mass is converted into energy ; then the liberated energy is equal to
(A) nine × 10 11 J (B) nine × 10 10 J
(C) six × 10 10 J (D) 8·5 × 10 10 J.
Ans :
24. Which reaction(s) in the sun account(s) for its huge amount of energy ?
(A) Fusion of heavy nuclei
(B) Fission of heavy nuclei
(C) Proton-proton chain and Carbon cycle
(D) Fusion of Carbon nuclei with Helium nuclei.
Ans :
25. What is the function of transparent glass plate used in the Solar Cooker ?
(A) Absorbs the Solar radiation
(B) Prevents the Solar radiation to go out of the wooden box
(C) Reflects the Solar radiation into the box
(D) Does not allow the heat energy to flow out of the box.
Ans :
26. In relation to the use of hard water, which of the subsequent does not reason energy
crisis ?
(A) Not using drinking water for other uses
(B) Not switching off the electrical instrument while not in use
(C) Not encouraging the use of other alternating energy sources
(D) Not using the improvised heating facilities.
Ans :
27. If you have to use electrical energy very efficiently, then you need to choose
(A) Fluorescent tubelight
(B) Compact Fluorescent ( tube ) lamp
(C) Incandescent lamp
(D) Electric arc lamp.
Ans :
28. Which of the subsequent elements provide its oxide quickly when kept in air ?
(A) Magnesium (B) Iron
(C) Sodium (D) Copper.
Ans :
29. Which of the subsequent is the accurate arrangement in the purification of copper by

Earning:   Approval pending.