Param Himalaya - परम हिमालय

Experiment 5 : To determine the angle of minimum deviation for a given prism by plotting a graph between angle of incidence and angle of deviation. Aim :  To determine the angle of minimum deviation for a given prism by plotting a graph between angle of incidence and angle of deviation. Apparatus :  A glass prism, drawing boards, white sheet of paper, paper pins, drawing pins, half metre rod and a protector, a drawing board. Theory :  A prism is a wedge-shaped body made from a refracting medium (glass) bounded by two plane faces inclined to each other at some angle. A ray PQ incident on face AB of prism ABC making angle of incident i and is refracted along QR making angle of refraction $r_1$. At point R, the ray is refracted along RS making angle of emergence e and angle of refraction $r_2$ an shown in Fig. A is angle of prism and $\delta$ is angle of deviation . It can be proved that$ $A + \delta = i + e$ and $A = r_1 + r_2$ At minimum deviation ($\delta = \delta_m$) $i ...

Experiment 6 : To determine refractive index of a glass slab using travelling microscope. Aim :  To determine refractive index of a glass slab using travelling microscope. Apparatus :  Travelling microscope, a glass slab, lycopodium powder, spirit level. Theory :  When an object mark X is placed at the bottom of the glass slab of refractive index n, it appears to be raised, when viewed obliquely. The actual depth of the mark X is called real depth and the raised depth is called apparent depth. $\therefore$ Refractive index of the glass slab $n= \frac{Real  \ depth}{Apparent \ depth}$ Procedure Calculate the vernier constant of the travelling microscope. Level the travelling microscope using a spirit level and the base screws. Set its axis to the vertical scale. Move the eye piece of the microscope so that a sharp image of the cross-wires is obtained. Put an ink mark X on the plateform of the travelling microscope (M) and focus the microscope on it. Note the reading $...

Experiment 6 :  To find the frequency of the A.C. mains with a sonometer (and an electromagnet). Aim :  To find the frequency of the A.C. mains with a sonometer (and an electromagnet). Apparatus :  A sonometer with a soft iron wire stretched over it, an electromagnet, a step down transformer, slotted half kilogram weights, a hanger, physical balance and a weight box. Theory :  When a wire of length l having mass m per unit length under tension T is made to vibrate, its fundamental frequency is given by : $n = \frac{1}{2l} \sqrt{\frac{T}{m}}$ When AC is passed in the coil of electromagnet, it is magnetised twice in every cycle, first with one of its face as N-pole and then with same face as S-pole. If the electromagnet is held close to the middle of the sonometer wire (Fig. 4.4), the wire will be attracted twice during each cycle towards the electromagnet and forced vibrations are produced. If the length of the sonometer wire between two wedges is so adjusted that it ...

Experiment 4: To determine resistance of a galvanometer by half deflection method and to find its figure of merit AIM :  To determine resistance of a galvanometer by half deflection method and to find its figure of merit Apparatus :  Moving coil galvanometer, two resistance boxes, two one way keys, connecting wires, sand paper and a battery. Theory :  Connect the galvanometer whose resistance is to be determined in series with a high resistance R as shown in Fig. 2.5. Close key K₁, keeping key K₂ open. If I current pass through the galvanometer, Then $I_g = \frac{E}{R+G}$ If $\theta$ is the deflection produced in the galvanometer, then $\frac{E}{R+G} = k\theta \quad \ldots \text{(i)}$ Now key $K_2$ is closed and shunt S is so adjusted that the deflection is $\frac{\theta}{2}$ If $I_g'$ is the current flowing through the galvanometer at this stage, then $I_g' = \frac{k\theta}{2} \quad \ldots \text{(ii)}$ At this stage, total resistance in the circuit $R' = R + \frac{GS}{G...

Experiment 3 (b) : To verify the laws of combination (parallel) of resistances using a metre bridge. Aim :  To verify the laws of parallel combination of resistances using meterbridge. Apparatus Required: a) Metrebridge. b) Two resistance wires. c) Resistance box. d) One-way key. e) Jockey. f) Galvanometer. g) Battery eliminator. Theory: A meterbridge works on the principle of Wheatstone's bridge. According to this principle of four resistances P, Q, R, S are connected & formed a closed network ABCD & a cell is connected between A & C, then galvanometer will show no deflection when bridge is balanced. To get balanced condition, P, Q, R & S should be adjusted. In balanced condition $\frac{P}{Q} = \frac{R}{S} \quad \text{— (1)}$ If unknown resistance 'X' is connected in the right gap of meterbridge & null point is obtained at a distance 'l' from left end of meterbridge. then Q is considered as X R is considered as l Hence, R will be considered as (...

Experiment 3 (a) : To verify the laws of combination (series) of resistances using a metre bridge. Aim: To verify the laws of combination (series) of Resistance using a Metre Bridge Apparatus: A metre bridge, a Leclanche cell (battery eliminator), a galvanometer, a resistance box, a jockey, two resistance wire or two resistance coils known resistances, a set square, sand paper and connecting wires. Theory: (i) The resistance (r) of a resistance wire or coil is given by  $r = \frac{(100-l)R}{l}$ where R is the resistance from the resistance box in the left gap and l is the length of the metre bridge wire from zero end upto balance point. (ii) When two resistance $r_1$ and $r_2$ are connected in series then their combined resistance $R_S = r_1 + r_2$ Procedure : Mark the two resistance coils as $r_1$ and $r_2$. To find $r_1$ and $r_2$ proceed same way as in experiment 1. Connect the two coils $r_1$ and $r_2$ in series as shown in figure in the right gap of metre bridge and find the r...

Experiment 2 : To find resistance of a given wire / standard resistor using metre bridge. Aim :  To find resistance of a given wire using Whetstone’s bridge (meter bridge) & hence determine the specific resistance of the material. Apparatus : A meter bridge (slide Wire Bridge), a galvanometer, a resistance box, a laclanche cell, a jockey, a one- way key, a resistance wire, a screw gauge, meter scale, set square, connecting wires and sandpaper. Theory :  Metre bridge apparatus is also known as a slide wire bridge. It is fixed on the wooden block and consists of a long wire with a uniform cross-sectional area. It has two gaps formed using thick metal strips to make the Wheatstone's bridge. Then according to Wheatstone's principle, we have: $$\frac{X}{R} = \frac{l}{(100-l)}$$ The unknown resistance can be calculated as: $$X = R \frac{l}{(100-l)}$$ Then the specific resistance of the material of the is calculated as: $$\rho = \frac{X.\pi.D^{2}}{4L}$$ Where,  * L is the le...