A person looking at a net of crossed wires is able to see the vertical direction more distinctly than the horizontal wires. What is the defect due to? How is such defect of vision corrected?

A current of 10 A flows around a closed path in a circuit which is in the horizontal plane as shown in the figure. The circuit consists oi eight alternating arcs of radii r_1=0.08m and r_2 =0.12m . Each subtends the same angle at the centre. a. Find the magnetic field produced by this circuit at the centre. b. An infinitely long straight wire carrying as current of 10 A is passing through the centre of the above circuit vertically with the direction of the current being into the pane of the circuit. what is the force acting on the wire at the centre due to the current in the circuit? What is the force acting on the arc AC and the straight segment CD due to the current at the centre?

A person with a myopic eye cannot see objects beyond 1.2 m distinctly. What should be the type of corrective lens to restore proper vision ?

Shows a smooth pair of thick metallic rails connected across a battery of emf epsilon having a negligible internal resistance. A wire ab of length l and resistance r can slide smoothly on the rails. The entire system lien in a horizontal plane and is immersed in a uniform vertical magnetic field B. At an instant t, the wire is given a small velocity v towards right. (a) find the current in it at this instant. What is the direction of the current? (b) What is the force acting on the wire at this instant? (c) Show that after some time the wire ab will slide with a constant velocity. Find this velocity.

Shows a smooth pair of thick metallic rails connected across a battery of emf epsilon having a negligible internal resistance. A wire ab of length l and resistance r can slide smoothly on the rails. The entire system lie in a horizontal plane and is immersed in a uniform vertical magnetic field B. At an instant t, the wire is given a small velocity v towards right. (a) find the current in it at this instant. What is the direction of the current? (b) What is the force acting on the wire at this instant? (c) Show that after some time the wire ab will slide with a constant velocity. Find this velocity.

A person cannot see distinctly object kept beyond 2 m. This defect can be corrected by using a lens of power

(a) A student suffering from myopia is not able to see distinctly the objects placed beyond 5 m . Two possible reasons due to which this defect of vision may have arisen. With the help of ray diagrams, explain : (i) Why the student is unable to see distinctly the objects placed beyond 5 m from his eyes. (ii) The type of corrective lens used to restore proper vision and how this defect is corrected by the use of this lens. (b) If in this case, numerical value of focal length of corrective lens is 5 m , find the power of the lens as per the new cartesion sign convention.

A straight horizontal conducting rod of length 0*45m and mass 60g is suspended by two vertical wires at its end. A current of 5*0A is set up in the rod through the wires. (a) What magnetic field should be set up normal to the conductor inorder that the tension in the wires is zero? (b) What will be the total tension in the wires if the direction of current is reversed, keeping the magnetic field same as before. (Ignore the mass of the wire) g=9*8ms^-2 .

Shows two long metal rails placed horizontally and parallel to each other at a separation i. A uniform magnetic field b exists in the vertically downward direction. A wire of mass m can slide on the rails. The rails are connected to a constant current source which drives a current I in the circuirt. The friction coefficient between the rails and the wire is mu . (a) What should be the minimum value of mu which can prevent the wire from sliding on the rails? (b) Describe the motion of the wire if the value of mu is half the value found in the previous part.

A rectangular loop PQRS made from a uniform wire has length a, width b and mass m. It is free to rotate about the arm PQ, which remains hinged along a horizontal line taken as the y-axis (see figure). Take the vertically upward direction as the z-axis. A uniform magnetic field vec(B) = (3 hat(i) + 4 hat(k)) B_(0) exists in the region. The loop is held in the x-y plane and a current I is passed through it. The loop is now released and is found to stay in the horizontal position in equilibrium (a) What is the direction of the current I in PQ? (b) Find the magnetic force on the arm RS. (c) Find the expression for I in terms of B_(0) , a, b and m

A rectangular loop PQRS made from a uniform wire has length a, width b and mass m. It is free to rotate about the arm PQ, which remains hinged along a horizontal line taken as the y-axis (see figure). Take the vertically upward direction as the z-axis. A uniform magnetic field vec(B) = (3 hat(i) + 4 hat(k)) B_(0) exists in the region. The loop is held in the x-y plane and a current I is passed through it. The loop is now released and is found to stay in the horizontal position in equilibrium (a) What is the direction of the current I in PQ? (b) Find the magnetic force on the arm RS. (c) Find the expression for I in terms of B_(0) , a, b and m