JEE Main Physics Mock Test- 6 - JEE MCQ

A particle of mass m is executing uniform circular motion on a path of radius r. If p is the magnitude of its linear momentum. The radial force acting on the particle is

The energy of a photon of light with wavelength 5000Å is approximately 2.5eV. This way the energy of an X-ray photon with wavelength 1Å would be

Electric field at the centroid of a triangle carrying q charge at each corner is

A particle of mass m and charge q is placed at rest in a uniform electric field E and then released. The kinetic energy attained by the particle after moving a distance y is

Two NOT gates are connected at the two inputs of a NAND gate. This combination will behave like

A body is projected at such an angle that the horizontal range is three times the greatest height. The angle of projection is

In the following question, a Statement of Assertion (A) is given followed by a corresponding Reason (R) just below it. Read the Statements carefully and mark the correct answer-
Assertion(A):Two bodies 1 and 2 exerting forces on each other.Force exerted on the body 1 by body 2 is F ^→ 12 and that exerted on the body 2 (by body 1) is F ^→ 21 . Then F ^→ 12 = − F ^→ 21 .
Reason(R):Force F ^→ 12 is of action and force F ^→ 21 is of reaction.

The M.I. of a body about the given axis is 1.2 kg x m² initially the body is at rest. In order to produce a rotational kinetic energy of 1500 joule an angular acceleration of 25 rad/sec²  must be applied about that axis for a duration of

Dimensional formula for torque is

The radionuclide ⁵⁶Mn is being produced in a cyclotron at a constant rate P by bombarding a manganese target with deutrons. ⁵⁶Mn has a half life of 2.5 hours and the target contains large number of only the stable manganese isotope ⁵⁵Mn. The reaction that produces ⁵⁶Mn is:

⁵⁵Mn+d→⁵⁶Mn+P

After being bombarded for a long time, the activity of ⁵⁶Mn becomes constant equal to 13.86×10s⁻¹. (Use ln2 = 0.693; Avogadro number = 6×10²³ atomic weight of ⁵⁶Mn = 56gm/mole)

Q. After a long time bombardment, number of ⁵⁶Mn nuclei present in the target depends upon 
(a) The number of ⁵⁶Mn nuclei present at the start of the process 
(b) Half life of the ⁵⁶Mn
(c) The constant rate of production P

A circular road of radius 1000 m has banking angle 45º. The maximum safe speed of a car having a mass 2000 kg will be, if the coefficient of friction between tyre and road is 0.5 :-

A bob of mass m, suspended by a string of length ℓ₁ is given a minimum velocity required to complete a full circle in the vertical plane. At the highest point, it collides elastically with another bob of mass m  suspended by a string of length ℓ₂, which is initially at rest. Both the strings are mass-less and inextensible. If the second bob, after collision acquires the minimum speed required to complete a full circle in the vertical plane, the ratio ℓ₁/ℓ₂ is.

A ring of radius 2m weights 100 kg. Its having pure rolling motion on a horizontal floor so that its centre of mass has a speed of 20 cm/s. If work done to stop it is xJ. Then x will be

2 kg ice at – 20°C is mixed with 5 kg water at 20°C. Then final amount of water in the mixture would be :
Given specific heat of ice = 0.5cal/g°C, specific heat of water = 1 cal/g°C,  Latent heat of fusion of ice = 80 cal/g. (in kg)

A diode having potential difference 0.5 V across its junction which does not depend on current, is connected in series with resistance of 20 Ω across source. If 0.1 A passes through resistance then what is the voltage of the source :-