List of top Physics Questions on General Principles and Processes of Isolation of Elements

A block of mass 1 kg is pushed up a surface inclined to horizontal at an angle of \( 60^\circ \) by a force of 10 N parallel to the inclined surface. When the block is pushed up by 10 m along the inclined surface, the work done against frictional force is: 
 


[Given: \( g = 10 \) m/s\( ^2 \), \( \mu_s = 0.1 \)] 
 

Two spheres A and B having respective charges 6 C and 12 C placed at a distance \( d \) repel each other by a force \( F \). The charge given to sphere A to reverse the force as \( -F \) is:
A particle of mass \( 2 \) kg is on a smooth horizontal table and moves in a circular path of radius \( 0.6 \) m. The height of the table from the ground is \( 0.8 \) m. If the angular speed of the particle is \( 12 \) rad/s, the magnitude of its angular momentum about a point on the ground right under the center of the circle is:

A gas can be taken from A to B via two different processes ACB and ADB. When path ACB is used, \( 60 J \) of heat flows into the system and \( 30 J \) of work is done by the system. If path ADB is used, the work done by the system is \( 10 J \). The heat flow into the system in path ADB is: 
 

An oil drop of radius \(1 \, \mu{m}\) is held stationary under a constant electric field of \(3.65 \times 10^4 \, {N/C}\) due to some excess electrons present on it. If the density of the oil drop is \(1.26 \, {g/cm}^3\), then the number of excess electrons on the oil drop approximately is:
[Take, g = 10 m/s2]

A parallel plate capacitor with plate area \(A\) and plate separation \(d = 2\) m has a capacitance of \(4\mu F\). The new capacitance of the system if half of the space between them is filled with a dielectric material of dielectric constant \(K = 3\) (as shown in the figure) will be: 
 


 

A body of mass \( M \) is at equilibrium under the action of four forces \( F_1, F_2, F_3 \), and \( F_4 \). If \( F_1 \) is removed from the body, then the body moves with an acceleration of:
The total energy of a gas mixture of one mole of oxygen and 3 moles of argon at a temperature \( T \) by neglecting vibrational modes is:
The de Broglie wavelength associated with the electrons accelerated by a potential of 81 V is lying in the region of electromagnetic waves:
If an ideal gas, in an insulated vessel, is allowed to expand into another similar evacuated vessel through a valve then:
If an ideal engine needs to transmit a torque of 200 Nm to maintain a rotor at a uniform angular speed of 300 rads\(^{-1}\), then the power required for the engine is:
In an incompressible liquid flow, mass conservation leads to: