Home/Class 12/Physics/

Question and Answer

Which of the following cannot be emited by radicative subsstances durind their decay ?
(A) protons
(B) Neutroes
(C) Helium nuclei
(D) Elactrons

Answer

Answer: A
The radioactive substance emit a - particle (Helium necleus) \(\beta-{p}{a}{r}{t}{i}{c}\le\) (electrons ) and neutrinoes
To Keep Reading This Answer, Download the App
4.6
star pngstar pngstar pngstar pngstar png
Review from Google Play
To Keep Reading This Answer, Download the App
4.6
star pngstar pngstar pngstar pngstar png
Review from Google Play
Correct3
Incorrect0
Watch More Related Solutions
The pitch of a screw gauge is 1 mm and there are \({100}\text{divisions}\) on circular scale. When faces \({A}\) and \({B}\) are just touching each without putting anything between the studs 32nd divisions of the circular scale (below its Zero) coincides with the reference line. When a glass plate is placed between the studs, the linear scale reads 4 divisions and the circular reads 16 divisions. Find the thickness of the glass plate. Zero of linnear scale is not hidden from circular scale when A and B touches each other.
The velocity of a projectile when it is at the greatest height is \({\left(\sqrt{{{2}/{5}}}\right)}\) times its velocity when it is at half of its greatest height. Determine its angle of projection.
A shaft is turning at \({65}{r}{a}{d}/{s}\) at time zero. Thereafter, angular acceleration is given by \(\alpha=-{10}{r}{a}{d}/{s}^{{{2}}}-{5}{t}{r}{a}{d}/{s}^{{{2}}}\)
Where \({t}\) is the elapsed time
(a). Find its angular speed at \({t}={3.0}\) s
(b). How much angle does it turn in these \({3}{s}\)?
A tube \({1.0}{m}\) long is closed at one end. A stretched wire is placed near the open end. The wire is \({0.3}{m}\) long and a mass of \({0.01}{k}{g}\) . It is held fixed at both ends and vibrates in its fundamental mode. It sets the air column in the tube into vibration at its fundamental frequency by resonance. Find
(a) the frequency of oscillation of the air column and
(b) the tension in the wire.
Speed of sound in air = \({330}{m}/{s}\) .
Identify the correct statement about the magnetic field lines.( )
A. These start always from closed loops
B. These lines always form closed loops 
C. Both A and B are correct
D. Both A and B are wrong
The dimensional forumla for thermal resistance is
(A) \({\left[{M}{L}^{{2}}{T}^{{-{3}}}{K}^{{-{1}}}\right]}\)
(B) \({\left[{M}{L}^{{2}}{T}^{{-{2}}}{A}^{{-{1}}}\right]}\)
(C) \({\left[{M}^{{-{1}}}{L}^{{-{2}}}{T}^{{3}}{K}\right]}\)
(D) \({\left[{M}{L}^{{2}}{T}^{{-{3}}}{K}^{{-{2}}}\right]}\)
Given that \(\int\frac{{{\left.{d}{x}\right.}}}{{\sqrt{{{2}{a}{x}-{x}^{{2}}}}}}={a}^{{n}}{{\sin}^{{-{1}}}{\left(\frac{{{x}-{a}}}{{{a}}}\right)}}\) where a is a constant. Using dimensional analysis. The value of n is
(A) 1
(B) -1
(C) 0
(D) none of the above.
Statement -1 : Distance travelled in nth second has the dimensions of velocity.
Statement -2 : Because it is the distancce travelled in one (particular) second.
(A) Statement -1 is true, Statement -2 is true , and Statement -2 is correct explanation of Statement -1.
(B) Statement -1 is true , Statement -2 is true, but Statement -2 is not a correct explanation of Statement -1.
(C) Statement-1 is true, but Statement -2 is false.
(D) Statement-1 is false, but Statement -2 is true.
What are the two angles of projection of a projectile projected with velocity of \({30}{m}/{s}\), so that the horizontal range is \({45}{m}\). Take, \({g}={10}{m}/{s}^{{{2}}}\).
Give an example of a physical wuantity (i) which has neigher unit nor direction (ii) has a dircetion but bot a vector (iii) can be either a vector or a scalar.

Load More