2<\/sub> = 5.0A, r = 4.0cm = 0.04m
\nl = 10cm = 0.10m
\nSince
\n
\n(direction is given by Fleming left-hand rule).<\/p>\nPlus Two Physics Moving Charges and Magnetism One Mark Questions and Answers<\/h3>\n
Question 1.
\nA straight wire of length 0.5 metre and carrying a current of 1.2 ampere is placed in uniform magnetic field of induction 2 tesla. The magnetic field is perpendicular to the length of the wire. Find the force on the wire is
\nAnswer:
\nF = i\/B = 1.2 \u00d7 0.5 \u00d7 2 = 1.2 N<\/p>\n
Question 2.
\nTo convert a galvanometer into a ammeter, one needs to connect a.
\n(a) low resistance in parallel
\n(b) high resistance in parallel
\n(c) low resistance in series
\n(d) high resistance in series
\nAnswer:
\n(a) low resistance in parallel<\/p>\n
Question 3.
\nA coil carrying electric current is placed in uniform magnetic field.
\n(a) torque is formed
\n(b) e.m.f is induced
\n(c) both a and b are correct
\n(d) none of these
\nAnswer:
\n(a) torque is formed<\/p>\n
Question 4.
\nDirection of motion of unit the positive test charge gives direction electric field. Direction of motion of…….gives direction of magnetic field.
\nAnswer:
\nUnit north pole.<\/p>\n
Question 5.
\nA magnetic system with zero dipole moment
\n(a) Solenoid
\n(b) current carrying coil
\n(c) current loop
\n(d) toroid
\nAnswer:
\n(d) Toroid.<\/p>\n
Question 6.
\nFind odd one regarding polarity solenoid, torroid, current carrying loop, bar magnet.
\nAnswer:
\nTorroid (In this case North and South pole are absent).<\/p>\n
Question 7.
\nThe nature of path when a charged particle is projected 30\u00b0 to the direction of magnetic field. (Helix, cycloid, straight line, parabola).
\nAnswer:
\nHelix<\/p>\n
Question 8.
\nWhat is solenoid?
\nAnswer:
\nAn insulated copper wire wound in the form of cylinder is called solenoid.<\/p>\n
Question 9.
\nWrite mathematical expression for ampere\u2019s theorem.
\nAnswer:
\n\u222bB.dl = \u00b50<\/sub>I<\/p>\nPlus Two Physics Moving Charges and Magnetism Two Mark Questions and Answers<\/h3>\n
Question 1.
\nThe figure shows a long straight conductor carrying a current I. A magnetic field is produced around the conductor.
\n
\nWhat is the magnitude of the magnetic induction at a point ‘P’ which is at a distant \u2018x\u2019 from the conductor?
\nWhat is the shape of the magnetic line of force?<\/p>\n
Answer:
\n1. B = \\(\\frac{\\mu_{0} I}{2 \\pi x}\\). Magnetic field is directed in to the plane of paper.<\/p>\n
2. Circular.<\/p>\n
Question 2.
\nA particle of mass 6.65 \u00d7 10-27<\/sup> kg having positive charge equal to two times of electron, moves with a speed of 6 \u00d7 105<\/sup> m\/s in a direction perpendicular to that of a given magnetic field of flux density 0.4 weber\/m2<\/sup>. Find the acceleration of the particle.
\nAnswer:
\n
\nq = 2e, v = 6 \u00d7 105<\/sup> m\/s
\nB = 0.4, m = 6.65 \u00d7 10-27<\/sup> kg
\n\u2234 acceleration,
\n
\na = 1.15 \u00d7 1013<\/sup> m\/s2<\/sup>.<\/p>\nQuestion 3.
\nClassify in to true or false.<\/p>\n
\n- The magnetic field in the middle of current carrying solenoid depends up on cross sectional area.<\/li>\n
- The magnetic field depends up on current.<\/li>\n
- The magnetic field depends up on the material of the core.<\/li>\n
- The magnetic field depends up on total numbers of turns per unit length.<\/li>\n<\/ol>\n
Answer:<\/p>\n
\n- False<\/li>\n
- True<\/li>\n
- True<\/li>\n
- True<\/li>\n<\/ol>\n
Question 4.
\nA short straight conductor carries current I<\/p>\n
\n- Write the expression for magnetic field due to this conductor.<\/li>\n
- Represent graphically the variation of magnetic field with distance from the wire.<\/li>\n<\/ol>\n
Answer:
\n1. dB = \\(\\frac{\\mu_{0}}{4 \\pi} \\frac{|d| \\sin \\theta}{r^{2}}\\)<\/p>\n
2.
\n<\/p>\n
Plus Two Physics Moving Charges and Magnetism Three Mark Questions and Answers<\/h3>\n
Question 1.
\nThe magnetic field along the axis of a circular coil is found to be B = \\(\\frac{\\mu_{\\mathrm{o}} \\mathrm{Ia}^{2}}{2\\left(\\mathrm{r}^{2}+\\mathrm{a}^{2}\\right)^{3 \/ 2}}\\)
\n1. What is the magnetic field along the axis if r>>a
\n2.<\/p>\n