Physics

A flying disc of radius r is moving with constant speed v? while rotating anticlockwise with angular speed v?/r along a curve PQ as shown below. Radius of curvature of curve at the instant is 4r. The magnitude of acceleration of point A at the instant is (3v₀²)/(nr). Find n.

Shown in figure is a block at rest having an inclined smooth groove in vertical plane. The horizontal surface is smooth. A ball of same mass as that of block at rest is released from top end. The time when ball will leave groove is √(nL/(2g√3)). Find n.

Radiation from hydrogen gas excited to first excited state is used for illuminating certain metallic plate. When the same plate is exposed to the radiation from some unknown hydrogen like gas excited to the same level it is found that de-Broglie wavelength of fastest photoelectron has decreased by 2.3 times. It is given that energy corresponding to longest wavelength of Lyman series of the unknown gas is 3 times the ionization energy of hydrogen gas (13.6eV). The work function (in eV) of the metallic plate is ______. [Take (2.3)² = 5.25]

Three capacitors each of capacitance C = 2μF are connected with a battery of emf 30V as shown in the figure. When the switch S is closed, the heat generated in circuit will be n/10 mJ. Find the value of n.

The given arrangement is in vertical plane and initially the springs are in natural length. The uniform rod is hinged at end O, about which it can freely rotate. The angular frequency of small oscillations of the rod is n/8 √(k/m). Find n. (Given: m = mass of rod, L = length of rod and k = mg/L)

Consider the given arrangement. The two slits S₁ and S₂ are illuminated by monochromatic light of wavelength λ. Slits S₃ and S₄ are at separation d₁ = λD/(3d), then ratio of maximum and minimum intensity on the screen will be

A radioactive β –emission. A detector records n β –particles in 2s and by next 2s (accumulatively) it records 1.1 n β –particle. Number of β –particles recorded by detector after a long time, is

A sine wave is travelling in a medium. The minimum distance between the two particles, always having same speed, is

A free particle having one electronic charge with initial kinetic energy 9 eV and de Broglie wavelength 1 mm enters a region of V₀ potential difference such that new de Broglie wavelength is now 1.5 mm. Then eV₀ is

A uniform rod, of mass m, length l and r radius of cross section, is rotated about an axis passing through one of its ends and perpendicular to its length with constant angular velocity ω in horizontal plane. If Y is the Young's modulus of the material of rod, the increase in its length due to rotation of rod is