Q1. Which of the following decrease in number in the human body due to Dengue fever?
Q2. A hydrogen-inflated polythene balloon is released from the surface of the earth. As the balloon rises to an altitude up in the atmosphere, it will—
(a) decrease in size
(b) flatten into a disc-like shape
(c) increase in size
(d) maintain the same size and shape
Q3. Ultrasonic waves are used for stirring liquid solutions because they—
(a) do not produce noise during the operation
(b) are easy to produce
(c) can produce perfectly homogeneous solution
(d) do not produce chemical reactions in the solution
Q4. Consider the following statements:
A body weighs less at the equator than at the poles because:
1. earth rotates about its axis.
2. the ice cap at the poles increases gravitational pull.
3. equatorial diameter is greater than the polar diameter.
4. of some unknown facts.
Which of the statements given above is/are incorrect?
(a) 1 and 2
(b) 3 only
(c) 1 and 3
(d) 4 only
Q5. Match List-I with List-II and select the correct answer given below:
A. Electron 1. Rutherford
B. Proton 2. J.J. Thomson
C. Neutron 3. Chadwick
D. Positron 4. Anderson
Codes: A B C D
(a) 2 1 3 4
(b) 4 3 1 2
(c) 2 1 4 3
(d) 4 3 2 1
Q6. The mad cow disease is caused by which of the following?
Q7. The credit of construction of first nuclear reactor goes to –
(a) Niels Bohr
Q8. Heavy water is used as a moderator in a nuclear reactor. The function of the moderator is—
(a) to control the energy released in the reactor.
(b) to absorb neutrons and stop the chain reaction.
(c) to cool the reactor.
(d) to slow down the neutrons.
Q9. Which one among the following elements/ions is essential in small quantities for development of healthy teeth but causes mottling of the teeth if consumed in higher quantities?
Q10. Which one of the following chemicals helps in fruit ripening?
Q11. A man inside a moving train tosses a coin, the coin falls behind him. The train is moving
(a) forward with a uniform speed
(b) backward with a uniform speed
(c) forward with deceleration
(d) forward with acceleration
Q12. Excessive exposure of humans to U V-rays results in—
(a) damage to immune system
(b) damage to lungs
(c) skin cancer
(d) peptic ulcers
Q13. Who was the discoverer of human blood groups?
Q14. Of the following, ELISA test is performed to test
Q15. Consider the following statements regarding diamond:
1. It is an allotrope of silicon.
2. It is a bad conductor of heat and electricity.
3. It is the hardest substance.
4. It burns to produce carbon dioxide.
Which of the statements given above are correct?
(a) 1, 2, 3 and 4
(b) 2, 3, and 4
(c) 1 and 2
(d) 1, 3 and 4