A air bubble of radius 1 cm in water has an upward acceleration 9.8 cm s^–2. The density of water is 1 gm cm^–3 and water offers negligible drag force on the bubble. The mass of the bubble is (g = 980 cm/s²).

A closed vessel contains 0.1 mole of a monoatomic ideal gas at 200 K. If 0.05 mole of the same gas at 400 K is added to it, the final equilibrium temperature (in K) of the gas in the vessel will be close to _______.

Particle A of mass m_A = $${m \over 2}$$ moving along the x-axis with velocity v₀ collides elastically with another particle B at rest having mass m_B = $${m \over 3}$$. If both particles move along the x-axis after the collision, the change $$\Delta $$$$\lambda $$ in de-Broglie wavlength of particle A, in terms of its de-Broglie wavelength ($$\lambda $$₀) before collision is :

On the x-axis and at a distance x from the origin, the gravitational field due a mass distribution is given by $${{Ax} \over {{{\left( {{x^2} + {a^2}} \right)}^{3/2}}}}$$ in the x-direction. The magnitude of gravitational potential on the x-axis at a distance x, taking its value to be zero at infinity, is: