You are sitting in a parked car and you notice a boy running towards the car in the side view mirror of the car. If the boy is running at a constant speed towards you, which option according to you is correct

The focal length of a thin lens in vacuum is f. If the material of the lens has refractive index \( \frac{3}{2} \), its focal length when immersed in water of refractive index \( \frac{4}{3} \) would be :

A charge q is moving with velocity \( \vec{v} \) in the presence of both electric field \( \vec{E} \) and magnetic field \( \vec{B} \). If velocity (\( \vec{v} \)), electric field (\( \vec{E} \)) and the magnetic field (\( \vec{B} \)) are mutually perpendicular. The charge will pass through the field undeflected if :

A capacitor of capacitance C is first charged by a battery of V volts. It is disconnected from the battery and is filled with a dielectric of dielectric constant K. The ratio of energy stored in the two cases, respectively will be

Match List-I with List-II

List-I (Uses of electromagnetic waves)	List-II (Type of electromagnetic waves)
(A) Aircraft navigation	(I) Infrared waves
(B) Cellular phones	(II) Microwaves
(C) Remote switches for TV sets	(III) Ultraviolet rays
(D) LASIK eye surgery	(IV)  Radio waves

Choose the correct answer from the options given below:

At one place on earth, the resultant magnetic field is 0.25 G and the angle of dip is 45°. The horizontal component of earth's magnetic field will be

Below given are some statements about electronic devices:
(A) Diodes can be used for rectifying an ac voltage.
(B) For semiconductors, band gap energy \( E_g > 3 \, eV \).
(C) By changing the external applied voltage, junction barriers can be changed.
(D) p-n junction is the 'key' to all semiconductor devices.
Choose the correct answer from the options given below:

Probability that a man speaks truth is \(\frac{3}{4}\). He throws a die and reports that it is a six. The probability that it is actually a

Answer the questions on the basis of passage given below :
As aldehydes ketones possess the carbonyl functional group, they show similar reactions. They exhibit nucleophilic addition reactions, reduction, oxidations, reactions due to alpha-Hydrogen atom, and many other reactions, like Cannizzaro reaction to electrophilic substitution reactions (in case of aromatic aldehydes ketones).
These reactions help in the preparation of a number of important compounds, like acetic acid, vinyl acetate, polymers and in perfume and dye industries.
Nucleophilic addition reactions form cyanohydrins, acetals, alcohols and N -substituted derivatives like imine, oxime, semicarbazone, phenylhydrazone Schiff's base. Reactions due to alpha-hydrogen atoms help in formation of aldols and alpha, beta-unsaturated aldehydes ketones.
Which of the following combinations of Grignard's reagent and carbonyl compound can give \(C _6 H _5- C ( OH )\left( CH _3\right)- CH \left( CH _3\right)_2\)
A. \(C _6 H _5 CH _2 MgBr +\left( CH _3\right)_2 CH - CHO\)
B. \(C _6 H _5 MgBr + CH _3- CO - CH \left( CH _3\right)_2\)
C. \(CH _3 MgBr + C _6 H _5- CO - CH \left( CH _3\right)_2\)
D. \(C _6 H _5- CO - CH _3+\left( CH _3\right)_2 CHMgBr\)
E. \(C _6 H _5 CH ( MgBr ) CH _3+\left( CH _3\right)_2 CO\)
Choose the correct answer from the option given below :

The speed of light in a material medium is given by :

If \(x=a \sec ^3 \theta, y=a \tan ^3 \theta\), then \(\frac{d y}{d x}\) at \(\theta=\frac{\pi}{3}\) is

Which one of the following options will express intermediate skin colour in an individual?

Which of the following enzyme is used during isolation of DNA from plant cell ?