List of practice Questions

Which among the following have a single unpaired electron?
N2, 02, CN-, O2-, C22- , N2-

How many molecules are present in 11.2 L of \(CO_{2}\) at STP?

Rosenmund reduction is used to convert acyl chlorides into:
Which of the following halides cannot be hydrolysed ?
The correct decreasing order of boiling point of hydrogen halides is
Male not responding to O-2, diagnosis ARDS. What is the role of IL-8 in ARDS?
Why did the peddler sign himself as Captain von Stahle?
How does Sophie include her brother Geoff in her fantasy of future?
The city folk who drove through the countryside hardly paid any heed to the roadside stand or to the people who ran it. If at all they did, it was to complain. Which lines bring this out? What was their complaint about?

Explain why the bulb would not glow in the arrangement shown in Fig. 9.13.

the bulb would not glow in the arrangement

Two immiscible liquids of refractive indices \( \frac{8}{5} \) and \( \frac{3}{2} \) respectively are put in a beaker as shown in the figure. The height of each column is 6 cm. A coin is placed at the bottom of the beaker. For near normal vision, the apparent depth of the coin is \( \frac{\alpha}{4} \) cm. The value of \( \alpha \) is ______.
Two immiscible liquids

The process that you saw in Activity 11.7 is used for purification of copper. A thin plate of pure copper and a thick rod of impure copper are used as electrodes. Copper from impure rod is sought to be transfered to the thin copper plate. Which electrode should be attached to the positive terminal of the battery and why?
electroplating
Express each of the following as a product of prime factors only in exponential form:
(i) 108 × 192 (ii) 270 (iii) 729 × 64 (iv) 768
A solid sphere of mass \( M \) and radius \( R \) is rolling without slipping with speed \( v \). Its total kinetic energy is:
A wooden block is initially at rest on a smooth surface. Now a horizontal force is applied on the block which increases linearly with time. The acceleration- time (a - t) graph for the block would be
A 2 kg brick is placed on an inclined plane of inclination 45°. The brick is at rest. The minimum coefficient of static friction is:
In a hydraulic lift force F is applied to balance 10 N load, diameter of effort arm is 14 cm and load arm is 1.4 cm. The F is equal to
A block of mass 50 kg is moving with speed of 10 m/s on a rough horizontal surface (friction coefficient of 0.3). Find the kinetic friction acting on the object.
A block of certain mass is placed on a rough inclined plane. The angle between the plane and the horizontal is $30^0$. The coefficients of static and kinetic frictions between the block and the inclined plane are 0.6 and 0.5 respectively. Then the magnitude of the acceleration of the block is [Take g=10 ms-2]
A body of mass 1 kg is suspended by a weightless string which passes over a frictionless pulley of mass 2 kg as shown in the figure. The mass is released from a height of 1.6m from the ground. With what velocity does it strike the ground ?
A block of mass 2 kg is placed on a rough inclined plane at an angle of 30 degrees. The coefficient of friction between the block and the plane is 0.2. If the block is released from rest, will it slide down the plane? Justify your answer with calculations.
A force of 20 N is applied to push a 4 kg block on a frictionless surface. What is the acceleration of the block?
If we walk on Ice its not easy for us why?
Subtract 3xy + 5yz – 7zx from 5xy – 2yz – 2zx + 10xyz
Electrostatics -4q and +2q charges dipole present in uniform electric field direction of rotation and net force?