Section A
Choose the best alternative of the following questions and write in the answer sheet.
[10 marks]
What is a variable that is kept constant during research period by researcher called?
(i) independent variable
(ii) dependent variable
(iii) controlled variable
(iv) extraneous variable
[1 mark]
What is the cause of systolic pressure of blood?
(i) due to excessive pressure created in the heart.
(ii) due to pressure produced in the left ventricle of the heart is transmitted to the artery.
(iii) due to contraction of artery at the time of contraction of left ventricle.
(iv) pressure produced at the time of contraction of ventricle.
[1 mark]
Which of the following organism has scientific name Cordyceps sinensis?
(i) Mugwort
(ii) Malabar nut
(iii) Caterpillar fungus
(iv) Turmeric
[1 mark]
What is the gravitational force of attraction exerted between A and B in the given figure?
(i) 8.34×10⁻¹⁶ N
(ii) 8.34×10⁻¹⁷ N
(iii) 8.34×10⁻¹⁸ N
(iv) 8.34×10⁻¹⁹ N
[1 mark]
On which principle is the submarine based on?
(i) Pascal's law
(ii) Archimedes' principle
(iii) law of flotation
(iv) Newton's law
[1 mark]
A student observed a spoon bent when it is dipped in a glass having water. He observed a fish kept in aquarium larger than actual size when she observed from outside. By which reasons shows condition observed?
(i) Due to velocity of water is more in water than in air.
(ii) Due to velocity of light changes when it enters into media having different densities.
(iii) Due to shape of object changes inside water.
(iv) Due to size of object changes inside water.
[1 mark]
A magnet as shown in the figure if inserted into the solenoid, the needle of galvanometer is deflected. What could be the reason for this?
(i) Motor effect
(ii) electromagnetic induction
(iii) Mutual induction
(iv) Magnetic effect of current
[1 mark]
What is X in the given chemical equation.
H₂SO₄ + 2NaOH → X + H₂O
(i) Na₂SO₃
(ii) NaSO₃
(iii) NaSO₂
(iv) Na₂SO₄
[1 mark]
Which of the following process is occur during smelting?
(i) Grinding
(ii) Refining
(iii) Reduction
(iv) Oxidation
[1 mark]
Why are detergents called 'soap less soap'?
(i) Do not produce lather with hard water like ordinary water.
(ii) Have the same chemical composition as soap.
(iii) Exhibits cleansing properties similar to soap and are effective even in hard water.
(iv) Exhibits cleansing properties like soap but chemically different from soap.
[1 mark]