Q1. Which zone of a candle flame is the hottest?
(a) Dark innermost zone
(b) Outermost zone
(c) Middle luminous zone
(d) Central zone
Q2. The image of the object that we see, forms on the retina of our eyes is—
(a) always erect
(b) always inverted
(c) erect or inverted depends upon the intensity of light
(d) erect or inverted depends upon the age of the person
Q3. Evening Sun is not as hot as the midday sun. What is the reason?
(a) In the evening, radiation travel slowly
(b) In the evening, the temperature of the sun decreases
(c) Ozone in atmosphere absorbs more light in the evening
(d) In the evening, radiations travel larger distance through atmosphere
Q4. A body is thrown vertically upwards and then falls back on the ground. When its potential energy is maximum?
(a) on the ground
(b) at the maximum height
(c) during the return journey
(d) both on the ground and at the maximum height
Q5. The magnet is strongest near the-
(a) on equator point from the poles of the magnet
(b) ends of the magnet
(c) centre of magnet
(d) None of the above
Q6. A body travelling with a speed of more than the velocity of sound in air is said to travel with—
(a) supersonic speed
(b) hypersonic speed
(c) ultrasonic speed
(d) infrasonic speed
Q7. Which of the special technique is used in ships to calculate the depth of ocean beds?
(c) sonic boom
Q8. What is the SI unit of electrical conductance?
Q9. Which of the following is a conductor of electricity?
(d) All of the above
Q10. Why is tungsten used exclusively for the filament of an incandescent lamp?
(a) Tungsten can be drawn into thin wires which in turn offer high resistance
(b) Tungsten has a fairly good resistivity
(c) The melting point of tungsten is very high
(d) All of these
Q11. Why ammeter is likely to burn out if you connect it in parallel?
(a) It has high voltage
(b) It has high resistance
(c) It has low resistance
(d) It has low voltage
Q12. What will happen to current passing through a resistor if the potential difference across its ends is doubled and the resistance is halved?
(a) Becomes four times
(b) Becomes halved
(c) Remain unchanged
(d) Becomes one fourth
Q13. Which of the following has the highest refractive index?
Q14. For a plane mirror, magnification (m)=________
(c) ± 1
(d) ≤ 0
Q15. We can see objects because of which phenomena?