Physics-
General
Easy
Question
A bullet of mass m and charge q is fired towards a solid uniformly charged sphere of radius R and total charge + q. If it strikes the surface of sphere with speed u, find the minimum speed u so that it can penetrate through the sphere. (Neglect all resistance forces or friction acting on bullet except electrostatic forces)
The correct answer is:
Related Questions to study
physics-
An infinite number of concentric rings carry a charge Q each alternately positive and negative. Their radii are 1, 2, 4, 8...... meters in geometric progression as shown in the figure. The potential at the centre of the rings will be
An infinite number of concentric rings carry a charge Q each alternately positive and negative. Their radii are 1, 2, 4, 8...... meters in geometric progression as shown in the figure. The potential at the centre of the rings will be
physics-General
physics-
If the electric potential of the inner metal sphere is 10 volt & that of the outer shell is 5 volt, then the potential at the centre will be :
If the electric potential of the inner metal sphere is 10 volt & that of the outer shell is 5 volt, then the potential at the centre will be :
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Potential difference between centre & the surface of sphere of radius R and uniform volume charge densityr within it will be :
Potential difference between centre & the surface of sphere of radius R and uniform volume charge densityr within it will be :
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A small particle of mass m and charge –q is placed at point P and released. If R >> x, the particle will undergo oscillations along the axis of symmetry with an angular frequency that is equal to
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physics-General
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The direction (q) of 
at point P due to uniformly charged finite rod will be
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The charge per unit length of the four quadrant of the ring is 
respectively. The electric field at the centre is
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physics-General
physics-
Six charges are placed at the corner of a regular hexagon as shown. If an electron is placed at its centre O, force on it will be:
Six charges are placed at the corner of a regular hexagon as shown. If an electron is placed at its centre O, force on it will be:
physics-General
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Four charges are arranged at the corners of a square ABCD, as shown. The force on a +ve charge kept at the centre of the square is
Four charges are arranged at the corners of a square ABCD, as shown. The force on a +ve charge kept at the centre of the square is
physics-General
chemistry-
All the boron trihalides except B may be prepared by direct reaction between the elements Boron trihalides consist of trigonal - planar BX3 molecules Unlike the halides of the other elements in the group they are monomeric in the gas, liquid and Sol. id states, BF3 and BCl3 are gases, BBr3 3Iis a volatile liquid and B is a Sol. Id Boron trihalides are Lewis acids because they form simple Lewis complexes with suitable bases, as in the reaction : 
However, boron chlorides, bromides and iodides are susceptible (sensitive) to protoly sis by mild proton sources such as water, alcohols and even amines; for example BCl3 undergoes rapid hydrolysis: 
It is supposed that the first step in the above reaction is the formation of the complex 
which then eliminates HCl and reacts further with water
Which of the following is the correct prediction about observed B–X bond length, in BX3 molecules ?
All the boron trihalides except B may be prepared by direct reaction between the elements Boron trihalides consist of trigonal - planar BX3 molecules Unlike the halides of the other elements in the group they are monomeric in the gas, liquid and Sol. id states, BF3 and BCl3 are gases, BBr3 3Iis a volatile liquid and B is a Sol. Id Boron trihalides are Lewis acids because they form simple Lewis complexes with suitable bases, as in the reaction : However, boron chlorides, bromides and iodides are susceptible (sensitive) to protoly sis by mild proton sources such as water, alcohols and even amines; for example BCl3 undergoes rapid hydrolysis: It is supposed that the first step in the above reaction is the formation of the complex which then eliminates HCl and reacts further with water
Which of the following is the correct prediction about observed B–X bond length, in BX3 molecules ?
chemistry-General
chemistry-
Statement-1 : Xenon forms fluorides
Statement-2 : 5 d-orbitals are available in xenon for valence shell expansion
Statement-1 : Xenon forms fluorides
Statement-2 : 5 d-orbitals are available in xenon for valence shell expansion
chemistry-General
chemistry-
Statement-1 : H3PO2 is a weak monobasic acid and is also strong reducing in nature
Statement-2 : 
Statement-1 : H3PO2 is a weak monobasic acid and is also strong reducing in nature
Statement-2 :
chemistry-General
chemistry-
Statement-1 : Electrovalency of oxygen is two (O2-)
Statement-2 : Dinegative anion of oxygen (O2-) is quite common but dinegative anion of sulphur (S2-) is less common
Statement-1 : Electrovalency of oxygen is two (O2-)
Statement-2 : Dinegative anion of oxygen (O2-) is quite common but dinegative anion of sulphur (S2-) is less common
chemistry-General
chemistry-
Statement-1 : H3PO3 is a dibasic acid and shows reducing characterStatement-2 :H3PO3 contains two OH– groups and one hydrogen atom directly attached to P atom
Statement-1 : H3PO3 is a dibasic acid and shows reducing characterStatement-2 :H3PO3 contains two OH– groups and one hydrogen atom directly attached to P atom
chemistry-General
chemistry-
Statement-1 : PbI4 is a stable compound.
Statement-2 : Pb2+ ions with concentrated Solution of KI forms a Sol. uble complex
Statement-1 : PbI4 is a stable compound.
Statement-2 : Pb2+ ions with concentrated Solution of KI forms a Sol. uble complex
chemistry-General
maths-
Consider the following statements 
and 
: S: Both 
x&cos 
are decreasing functions in the interval 
.
R: If a differentiable function decreases in an interval 
, then its derivative also decreases in Which of the following is true ?
Consider the following statements and : S: Both x&cos are decreasing functions in the interval .
R: If a differentiable function decreases in an interval , then its derivative also decreases in Which of the following is true ?
maths-General
