COMEDK Mock Test - 7 - JEE MCQ

The truth table given below is for (A and B are the inputs, Y is the output). What type of GATE it will form?

A second pendulum is mounted in a space shuttle. Its period of oscillations will decrease when rocket is:

The difference of speed of light in the two media A and B (v_A - v_B) is 2.6 × 10⁷ m/s. If the refractive index of medium B is 1.47, then the ratio of refractive index of medium B to medium A is: (Given: Speed of light in vacuum, c = 3 × 10⁸ ms^-1)

An ideal transformer has 500 and the 1000 turns in the primary and the secondary coil. If the DC voltage of 120 V is applied to the primary coil, then the emf produced at the secondary coil will be:

The energy released by the fission of one uranium atom is 200 MeV. The number of fissions required per second to produce 3.2 W of power is

The activity of a radioactive sample falls from 700 s^-1 to 500 s^-1 in 30 minutes. Its half life is close to:

A cylindrical solid of length L and radius a is having varying resistivity given by ρ = ρ₀x where ρ₀ is a positive constant and x is measured from the left end of the solid. The cell shown in the figure is having emf V and negligible internal resistance. The electric field as a function of x is best described by:

An object of mass 5 kg is thrown vertically upwards from the ground. The air resistance produces a constant retarding force of 10 N throughout the motion. The ratio of time of ascent to the time of descent will be equal to [Use g = 10 ms^-2]

For a gas, the difference between the two specific heats at constant pressure and constant volume is 4150 J kg^-1 K^-1 and their ratio is 1.4. What is the specific heat of the gas at constant volume in units of J kg^-1 k^-1?

The magnifying power of a telescope with tube length 60 cm is 5. What is the focal length of its eye-piece?

A compound A has molecular formula C₂Cl₃OH. It reduce Fehling's solution and on oxidation gives a monocarboxylic acid B. A is obtained by the action of Cl₂ on ethyl alcohol. A is

The heats of dissociation (k.cals/mole) of methane and ethane are 360 and 620 respectively. From these, C - C bond energy (k.cals/mole) in ethane can be evaluated as

When the densities of the ore particles and gangue particles are different, then the ore is concentrated by

Which of the following reacts rapidly with oxygen in air at ordinary temperature

Propene is reacted with HBr in presence of peroxide, the product is

Which one of the following compounds is not a vitamin?

Scurvy is caused due to deficiency of

The mass of 112 cm³ of CH₄ gas at STP is

In a reversible reaction, the catalyst

The IUPAC name of CH₃-C≡C-CH(CH₃)₂ is

Copper sulphate dissolves in excess of KCN to give

Let two points be A(1, -1) and B(0, 2). If a point P(x', y') be such that the area of ΔPAB = 5 sq. units and it lies on the line 3x + y - 4λ = 0, then a value of λ is

In a triangle ABC, if  then the projection of the vector  is equal to:

If c is a point at which Rolle's theorem holds for the function f(x) = log_e  in the interval [3, 4], where α ∈ R, then f''(c) is equal to

Where [t] denotes greatest integer ≤ t. If m is the number of points where f is not continuous and n is the number of points where f is not differentiable, then the ordered pair (m, n) is

The line y = x + 1 meets the ellipse  at two points P and Q. If r is the radius of the circle with PQ as diameter, then (3r)² is equal to:

Let . If  , then T + n(S) is equal to: