JEE(MAIN) Physics Mock Test - 8

Two bodies of mass 10 kg and 5 kg moving in concentric orbits of radii R and r such that their periods are the same. Then the ratio between their centripetal acceleration is

An electric dipole is placed along the X-axis at the origin O. A point P is at a distance of 20 cm from this origin such that OP makes an angle π/3 with the X axis. If electric field at P makes an angle θ with X-axis, the value of θ is

A semi circle arc of radius 'a' is charged uniformly and the charge per unit length is λ. The electric field at its centre is

The figure shows the symbol of a

Which of the following equations is definitely wrong?

A 2 kg mass is rotating on a circular path of radius 0.8 m with angular velocity of 44 rad-s^-1. If radius of the path becomes 1 m, then value of angular velocity will be

Which is not a unit of electric field

In a mixture of H−He⁺ gas (He⁺ is singly ionized He atom) , H atoms and He⁺ ions are excited to their respective first excited states. Subesquently, H atoms transfer their total excitation energy to He⁺ ions (by collisions). Assume that the Bohr model of atom is exactly vaild.

Q. The quantum number n of the state finally populated in He⁺ ions is

In a mixture of H−He⁺ gas (He⁺ is singly ionized He atom) , H atoms and He⁺ ions are excited to their respective first excited states. Subesquently, H atoms transfer their total excitation energy to He⁺ ions (by collisions). Assume that the Bohr model of atom is exactly vaild.

Q. The wavelength of light emitted in the visible region by He⁺  ions after collisions with H atoms is

In an Young's double slit experiment setup, as shown in the figure, the light source executes simple harmonic motion between P and Q according to the equation x=Asinωt, s being the mean position. Assume d→O and A≪L. ω is small enough to neglect Doppler effect. If the source were stationary at s, intensity at O would be I₀.

Q. When the source comes towards the point Q,

In an Young's double slit experiment setup, as shown in the figure, the light source executes simple harmonic motion between P and Q according to the equation x=Asinωt, s being the mean position. Assume d→O and A≪L. ω is small enough to neglect Doppler effect. If the source were stationary at s, intensity at O would be I₀.

Q. The fringe width β can be expressed as

In an Young's double slit experiment setup, as shown in the figure, the light source executes simple harmonic motion between P and Q according to the equation x=Asinωt, s being the mean position. Assume d→O and A≪L. ω is small enough to neglect Doppler effect. If the source were stationary at s, intensity at O would be I₀.

Q. The fractional change in intensity of the central maximum as function of time is

A 5.0 μ F capacitor is charged to a potential difference of 800 V and discharged through a conductor. The energy given to the conductor during the discharge is

A charge is moving in a uniform magnetic field in a circular path of radius R. If the energy of the particle is doubled, the new radius is

A uniform rod of length l is freely pivoted at one end. It is initially held horizontally and then released from rest. The angular velocity at the instant when the rod is vertical is

Two identical thin conducting spherical shells of radius R carry equal negative charges of magnitude Q sprayed uniformly on their surfaces. The distance AB between their centres is 4R. The electric field at a point P(fig.) at distance R/2 from the centre A of the first sphere is

An electric iron draws 5 amp, a TV set draws 3 amp and a refrigerator draws 2 amp from a 220 volt main line. The three appliances are connected in parallel. If all the three are operating at the same time, the fuse used may be of

A proton of mass m and charge + e is moving in a circular orbit of magnetic field with energy 1 Me V. What should be the energy of α-particle (mass 4 m and charge + 2 e) so that it can revolve in the path of same radius as that of proton.