ASK Rare Notes – Study Notes & Exam Preparation

i. Which statement is true about the magnetic poles? (a) unlike poles repel (b) like poles attract (c) magnetic poles do not effect each other (d) a single magnetic pole does not exist ... Answer is (d)  a single magnetic pole does not exist All Magnets have two poles, a north pole and a south pole.A magnet with a single magnetic pole does not exist Show Answer ii. What is the direction of the magnetic field lines inside a bar magnet? (a) from north pole to south pole (b) from south pole to north pole (c) from side to side (d) there are no magnetic field lines ... Answer is (b)  from south pole to north pole Magnets have two poles, a north pole and a south pole. The magnetic field is represented by field lines that start at a magnet's north pole and end at the south pole both inside and outside of the bar magnets Show Answer iii. The presence of a magnetic field can be detected by a ...

i. An electric current in conductors is due to the flow of (a) positive ions (b) negative ions (c) positive charges (d) free electrons ... Answer is (d)  free electrons A metallic conductor has a large number of free electrons in it. These free electrons begin to drift from the low potential to the high potential region, when a potential difference is applied across the ends of a metallic wire. Thus, Current in a conductor is due to motion of the free electrons. Show Answer ii. What is the voltage across a 6 Ω resistor when 3A of current passes through its? (a) 2 V (b) 9 V (c) 18 V (d) 36 V ... Answer is (c)  18 V Given: Resistance (R) = 6 Ω Current ( I ) = 3 A To Find: Voltage V = ? Solution: V = I x R = 3 A x 6 Ω = 18 volts Show Answer iii. What happens to the intensity or the brightness of the lamps connected in series as more and more lamps are added? (a) increases (b) d...

i. A positive electric charge (a) attract other positive charge (b) repels other positive charge (c) attracts a neutral charge (d) repels a neutral charge ... Answer is (b)  repels other positive charge Charge is a basic property of matter. According to the property of charges, Like charges repel each other; while unlike charges attract each other. Thus a positive electric charge will repels other positive charge. Show Answer ii. An object gains excess negative charge after being rubbed against another object, which becomes (a) neutral (b) negatively charged (c) positively charged (d) either a, b or c ... Answer is (c)  positively charged If one object gain excess negative charge ( i.e. gain of electrons) after being rubbed against another object. The other Object will definitely losses electron thus the object will excess of positive charge (proton). Show Answer iii. Two uncharged objects A...

i. Which of the following quantities is not changed during refraction of light? (a) its direction (b) its speed (c) its frequency (d) its wavelength ... Answer is (c)  its frequency Frequency of light does not change on refraction. When a ray of light passes from one medium to another, its direction (or path) changes because of change in speed of light from one medium to another. Show Answer ii. A converging mirror with a radius of 20 cm creates a real image 30 cm from the mirror. What is the object distance? (a) -5.0 cm (b) -7.5 cm (c) -15 cm (d) -20 cm ... Answer is (c)  -15 cm According to the New Cartesian Sign Convention of Concave and Convex Lens, the distances measured in the direction opposite to the direction of incident light are taken as negative(-ve). Distances measured in the same direction as the incident light are taken as positive (+ve). Given: Radius of Curvature R= 20 cm so Focal Le...

i. Which is an example of a longitudinal wave? (a) sound wave (b) light wave (c) radio wave (d) water wave ... Answer is (a)  sound wave In a longitudinal wave the particle displacement is parallel to the direction of wave propagation. e.g. Sound waves While, in a Transverse wave the particle displacement is perpendicular to the direction of wave propagation. e.g. Light waves, Radio waves, Water waves. Show Answer ii. How does sound travel from its source to your ear? (a) by changes in air pressure (b) by vibrations in wires or strings (c) by electromagnetic waves (d) by infrared waves ... Answer is (a)  by changes in air pressure A sound wave is a pressure wave; in which regions of high (compressions) and low pressure (rarefactions) are established as the result of the vibrations of the sound source. Show Answer iii. Which form of energy is sound? (a) electrical (b) mechanical ...