On interchanging the resistances, the balance point of a meter bridge shifts to the left by 10 cm. The resistance of their series combination is 1 k$$\Omega $$. How much was the resistance on the left slot before interchanging the resistances?

A granite rod of 60 cm length is clamped at its middle point and is set into longitudinal vibrations. The density of granite is 2.7 $$\times$$ 10³ kg/m³ and its Young’s modulus is 9.27 $$\times$$ 10¹⁰ Pa. What will be the fundamental frequency of the longitudinal vibrations ?

A silver atom in a solid oscillates in simple harmonic motion in some direction with a frequency of 10¹²/sec. What is the force constant of the bonds connecting one atom with the other? (Mole wt. of silver = 108 and Avogadro number = 6.02 × 10²³ gm mole^–1)

Two batteries with e.m.f 12 V and 13 V are connected in parallel across a load resistor of 10 $$\Omega $$. The internal resistances of the two batteries are 1 $$\Omega $$ and 2 $$\Omega $$ respectively. The voltage across the load lies between :