Physics

A uniform conducting wire of length 12a and resistance ' R ' is wound up as a current
carrying coil in the shape of,
(i) an equilateral triangle of side ' a '.
(ii) a square of side ' a '.
The magnetic dipole moments of the coil in each case respectively are:

A step down transformer connected to an ac mains supply of 220 V is made to operate at 11 V, 44 W lamp. Ignoring power losses in the transformer, what is the current in the primary circuit?

For the given circuit, the input digital signals are applied at the terminals A, B and C. What would be the output at the terminal y?

A point object is placed at a distance of 60 cm from a convex lens of focal length 30 cm. If a plane mirror were put perpendicular to the principal axis of the lens and at a distance of 40 cm from it, the final image would be formed at a distance of:

Three resistors having resistances r₁,r₂ and r₃ are connected as shown in the given circuit. The ratio i₂/i₃ of currents in terms of resistances used in the circuit is:

The number of photons per second on an average emitted by the source of monochromatic light of wavelength 600 nm, when it delivers the power of 3.3 * 10⁻³
watt will be : h = 6.6 * 10⁻³⁴Js)

The effective resistance of a parallel connection that consists of four wires of equal length, equal area of cross-section and same material is 0.25Ω. What will be the effective resistance if they are connected in series?

A cup of coffee cools from 90°C to 80°C in t minutes, when the room temperature is 20°C.
The time taken by a similar cup of coffee to cool from 80°C to 60°C at a room temperature same at 20°C is:

If force [F], acceleration [A] and time [T] are chosen as the fundamental physical quantities. Find the dimensions of energy.

The equivalent capacitance of the combination shown in the figure is: