List of practice Questions

The oscillation of a body on a smooth horizontal surface is represented by the equation,
X = A cos (ωt)
where X = displacement at time t
        ω = frequency of oscillation
Which one of the following graphs shows correctly the variation 'a' with 't'?
Here a acceleration at time t
T = time period

Light with an energy flux of 25 × 10⁴ Wm^-2 falls on a perfectly reflecting surface at normal incidence. If the surface area is 15 cm², the average force exerted on the surface is:

A radio isotope 'X' with a half life 1.4 × 10⁹ years decays to 'Y' which is stable. A sample of the rock from a cave was found to contain 'X' and 'Y' in the ratio 1:7. The age of the rock is:

A transformer having efficiency of 90% is working on 200 V and 3 kW power supply. If the current in the secondary coil is 6 A, the voltage across the secondary coil and the current in the primary coil respectively are:

When the energy of the incident radiation is increased by 20%, the kinetic energy of the photoelectrons emitted from a metal surface increased from 0.5 eV to 0.8 eV. The work function of the metal is

In this question, there are two words/set of letters/numbers to the left of the sign :: which are connected in some way. The same relationship obtains between the third words/set of letters/numbers and one of the four alternatives under it. Find the correct alternative in question.
DRIVEN : EIDRVN :: BEGUM : ?

$N_2$ and $O_2$ are converted into mono anions, $N_2^{-}$ and $O_2^{-}$ respectively. Which of the following statements is wrong ?

Which one of the following is an example of a thermosetting polymer?

Copper of fixed volume 'V' is drawn into wire of length 'l'. When this wire is subjected to a constant force 'F', the extension produced in the wire is 'Δl'. Which of the following graphs is a straight line?

Following figures show the arrangement of bar magnets in different configurations. Each magnet has magnetic dipole moment \(\overrightarrow{m}\). Which configuration has highest net magnètic dipole moment?

The given graph represents V – I characteristic for a semiconductor device

Which of the following statement is correct?

What products are formed when the following compound is treated with Br₂ in the presence of FeBr₃?

Which property of colloids isnot dependent on the charge on colloidal particles?

For a given exothermic reaction, K_p and K'_P are the equilibrium constants at temperatures T₁ and T₂, respectively. Assuming that heat of reaction is constant in temperature range between T₁ and T₂, it is readily observed that:

For the reversible reaction :
\(N_2(g) + 3H_2(g) ⇋ 2NH_3(g) + \text {Heat}\)
The equilibrium shifts in forward direction :

Which of the following statements is correct for the spontaneous adsorption of a gas?

An elemental crystal has a density of $8570 \,kg / m ^{3}$. The packing efficiency is $0.68$. The closest distance of approach between neighbouring atom is $2.86 \,?$. What is the mass of one atom approximately?

Which of the following hormones is produced underthe condition of stress which stimulates glycogenolysis in the liver of human beings?

Which of the following will not be soluble in sodiumhydrogen carbonate?

Which one is most reactive towards Nucleophilic addition reaction?

Which of the following organic compounds has same hybridization as its combustion product CO2 ?

\(Be^{2+}\) is isoelectronic with which of the following ions?

A speeding motorcyclist sees traffic jam ahead of him. He slows down to 36 km/hour. He finds that traffic has eased and a car moving ahead of him at 18 km/hour is honking at a frequency of 1392 Hz. If the speed of sound is 343 m/s, the frequency of the honk as heard by him will be :

A body of mass (4m) is lying in x-y plane at rest. It suddenly explodes into three pieces. Two pieces, each of mass (m) move perpendicular to each other with equal speeds (v). The total kinetic energy generated due to explosion is :

Which form coloured salts :