28/03/2020 Magnetic Fields(Senior Class Physics Study by Topics) 28/03/2020 0Comments by Gate Academy Welcome to your Magnetic Fields(Senior Class Physics Study by Topics) NAME EMAIL PHONE NUMBER 1. Which of the following statements about the orientation and effects of Earth's magnetic field is not true? A compass needle always indicates the direction of true north. The geographic North Pole of Earth is near the magnetic south pole. A compass needle that can rotate both perpendicularly and parallel to the surface of Earth, points down at the magnetic south pole. The geographic South Pole of Earth corresponds to the magnetic north pole. 2. Which of the following statements correctly describes the behavior of magnets? Like poles repel each other, and unlike poles attract each other. Like poles attract each other, and unlike poles repel each other. Both like and unlike poles can attract and repel each other depending on the surrounding materials. None of the above. 3. Weakest force in nature is? Gravitational force Weak force Electric force Magnetic force 4. The ratio of magnetic force to electric force on a charged particle getting undeflected in a field is? 2 4 0 1 5. Where are the two poles located at? Asia & Russia None of the above Canadic Ocean & Off the cost of the Antarctica 6. Can we see magnetic flux lines? Depends on the strength of the field Only when the field strength is very large Yes No 7. The relation between the direction of current and the direction of magnetic field is ________ Opposite direction Perpendicular Unrelated Same direction 8. Which, among the following qualities, is not affected by the magnetic field? Stationary charge Current flowing in a conductor Change in magnetic flux Moving charge 9. Which of the following statements about magnetic fields is not true? Magnetic fields are vector quantities. Magnetic field strength increases as the distance from the magnetic source increases. Magnetic fields are regions in which magnetic forces can be detected. Magnetic fields have both magnitude and direction. 10. According to Flemming’s left hand rule, the middle finger denotes? Direction of force Direction of current Direction of force as well as current Direction of magnetic field 11. Electric currents are measured in...? Amperes Nanoteslas Microteslas Newtons 12. What describes ΦM? The number of field lines that cross a certain area ABcosθ Magnetic flux All of the above 13. What is our best evidence that Earth has a magnetic field? Earth's oceans all have currents A compass needle lines up with it. All things fall toward Earth's center. Winds blow from east to west. 14. According to Flemming’s left hand rule, the index finger denotes? Direction of force Direction of magnetic field Direction of current Direction of force as well as current 15. How is the intensity of the earth's magnetic field measured? Ampere Newton Gauss Tesla 16. A charged particle moves with velocity v in a magnetic field B. The magnetic force on the particle is a maximum when v is zero True False 17. Which of the following statements about magnetic field lines is not true? Magnetic field lines have no beginning or end. Magnetic field lines appear to begin at the north pole of a magnet. Magnetic field lines form open or closed loops. Magnetic field lines appear to end at the south pole of a magnet. 18. What is the magnetic field outside a solenoid? Zero Infinity Double the value of the field inside Half the value of the field inside 19. The Earth Magnetic Field contains: Its magnetic is shaped like a bar 2 poles Liquid iron All of the above 20. How is Earth’s magnetic field similar to that of a magnet? It is shaped like a horseshoe. It is made in Earth's core. It has North and South Poles. It is hundreds of miles long. 21. What happens when two north poles of magnets are placed together? The strength of the magnet is doubled. They cancel each other out. They repel. They attract. 22. If the flow of electric current is parallel to the magnetic field, the force will be _____ Zero Half the original value Maximum Infinity 23. What is the strength of magnetic field known as ________ Density Flux Magnetic strength Magnetic flux density 24. Lines signify the strength of magnetic fields. If the lines are denser the magnetic field is...? Stronger Normal Slower Weaker 25. Which of these is most likely to attract? Unlike poles Like poles South poles North poles 1 out of 25 Time is Up! Time's up