List of practice Questions

A metal wire has a length of 2 meters and a resistance of \( 10 \, \Omega \). If the length of the wire is doubled, while keeping the material and cross-sectional area the same, what will be the new resistance?
In a p-n junction diode, if the forward bias voltage is increased, how does the current flowing through the diode change?
A ball is thrown vertically upwards with an initial speed of 10 m/s. Calculate the maximum height reached by the ball. (Assume \( g = 9.8 \, \text{m/s}^2 \))
Following representations P, Q and R denote few steps of Griffith Experiment. Identify the correct one(s)
P. R strain → Inject into mice → Mice die
Q. S strain (Heat killed) → Injected into mice → Mice die
R. R strain → Inject into mice → Mice live
Identify the incorrect match respect to recently extinct animals and their place extinction according to IUCN Red list
Two finite sets have m and n elements respectively. The total number of subsets of the first set is 56 more than the total number of subsets of the second set. The values of m and n respectively are
Mixing of $N_2$ and $H_2$ form an ideal gas mixture at room temperature in a container. For this process, which of the following statement is true?
Choose the correct spelling:
If A.M. and G.M. of roots of a quadratic equation are 5 and 4 respectively, then the quadratic equation is

Give the structures of A, B and C in the following reactions: 

The enrolment in a school during six consecutive years was as follows:
1555, 1670, 1750, 2013, 2540, 2820
Find the mean enrolment of the school for this period.
The author’s grandmother was a religious person. What are the different ways in which we come to know this?
The number of atoms in 4.5 g of a face-centred cubic crystal with edge length 300 pm is :
(Given density=10gcm-3 and NA=6.022×1023).
Two chairs (A and B) are in an empty room overnight. Chair A is made of steel while chair B is made of wood. In the night and in the morning, the temperature of the room is 290 K. In the morning, a person chooses between Chair A and Chair B as the seat by feeling (touching) the chair and choosing one which feels warmer. 
Person chooses __ (BLANK-1) __ as it feels warmer because __ (BLANK-2)___ has __(BLANK-3)___ ___ (BLANK-4)____ than ___(BLANK-5)___ .
The ratio of molar specific heats of oxygen is
The figure shows variation of R,XL and XC with frequency ' f ' in a series LCR circuit. Then for what frequency point is the circuit capacitive?
LCR circuit
In the figure, a conducting ring of certain resistance is falling towards a current carrying straight long conductor. The ring and conductor are in the same plane. Then the
a conducting ring of certain resistance
In alpha particle scattering experiment, if v is the initial velocity of the particle, then the distance of closest approach is d. If the velocity is doubled, then the distance of closest approach becomes
Electromagnetic waves are incident normally on a perfectly reflecting surface having surface area A. If I is the intensity of the incident electromagnetic radiation and c is the speed of light in vacuum, the force exerted by the electromagnetic wave on the reflecting surface is
A p -n junction diode is connected to a battery of emf 5.7 V in series with a resistant 5kΩ such that it is forward biased. If the barrier potential of the diode is 0.7 V, neglecting the diode resistance, the current in the circuit is
The natural logarithm of the activity R of a radioactive sample varies with time t as shown. At t=0, there are N0 undecayed nuclei. Then N0 is equal to [Take e2= 7.5]
A particle of mass 500 g is at rest. It is free to move along a straight line. The power delivered to the particle varies with time according to the following graph :
The momentum of the particle at t=5s is
In the circuit shown, the end A is at potential V0 and end B is grounded. The electric current I indicated in the circuit is
the end A is at potential V0 and end B is grounded
A body has a charge of -3.2μC . The number of excess electrons it has is
A coil having 9 turns carrying a current produces magnetic filed B1 at the centre. Now the coil is rewounded into 3 turns carrying same current. Then the magnetic field at the centre B2=