Question
A molecule. of hydrogen contains two protons and two electrons. The nuclear force between these two protons is always neglected while discussing the behaviour of a hydrogen molecule. Why?

Answer

Inside the nucleus, two protons exert nuclear force on each other. These forces are short-ranged (a few fm), strong and attractive forces. They also exert electrostatic repulsive force (long-ranged). While discussing the behaviour of a hydrogen molecule, the nuclear force between the two protons is always neglected. This is because the separation between the two protons in the molecule is ~70pm which is much greater than the range of the nuclear force.

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Similar questions

A uniform rod of mass 300g and length 50cm rotates at a uniform angular speed of 2rad/s about an axis perpendicular to the rod through an end. Calculate:
  1. The angular momentum of the rod about the axis of rotation.
  2. The speed of the centre of the rod.
  3. Its kinetic energy.
Two identically charged particles are fastened to the two ends of a spring of spring constant $100Nm^{-1}$ and natural length 10cm. The system rests on a smooth horizontal table. If the charge on each particle is $2.0 \times 10^{-8}C,$ find the extension in the length of the spring. Assume that the extension is small as compared to the natural length. Justify this assumption after you solve the problem.
A capacitor is connected to an alternating-current source. Is there a magnetic field between the plates?
Figure shows a metallic square frame of edge a in a vertical plane. A uniform magnetic field B exists in the space in a direction perpendicular to the plane of the figure. Two boys pull the opposite corners of the square to deform it into a rhombus. They start pulling the corners at t = 0 and displace the corners at a uniform speed u.
  1. Find the induced emf in the frame at the instant when the angles at these corners reduce to 60°.
  2. Find the induced current in the frame at this instant if the total resistance of the frame is R.
  3. Find the total charge which flows through a side of the frame by the time the square is deformed into a straight line.
$a.$ Write the relationship between mobility and drift velocity in a current carrying conductor.
$b.$ Two aluminium wires have their lengths in the ratio $2 : 3$ and radii in the ratio $1 : 3.$ These are connected in parallel across a battery of emf $E$ and of negligible internal resistance. Find the ratio of drift velocities of the electrons in the two wires.
The radionuclide $^{11}C$ decays according to
$^{11}_{6}\text{C}\rightarrow^{11}_{5}\text{B}+\text{e}^{+}+\text{v}:\ \text{T}_{1/2}=20.3 \text{ min}$
The maximum energy of the emitted positron is 0.960 MeV.
Given the mass values:
$\text{m}(^{11}_{6})=10=11.011434\text{ u and m}(^{11}_{6}\text{B})=11.009305\text {u}.$
calculate Q and compare it with the maximum energy of the positron emitted.

Figure shows a typical circuit for a low-pass filter. An AC input $V_{i }= 10mV$ is applied at the left end and the output $V_0$ is received at the right end. Find the output voltage for ν = 10kHz, 1.0MHz and 10.0MHz. Note that as the frequency is increased the output decreases and, hence, the name low-pass filter.
Why are the magnification properties of microscopes and telescopes defined in terms of the ratio of angles and not in terms of the ratio of sizes of objects and images?
Define semiconductors on the basis of energy band theory. What are the charge carriers in semiconductor? What do semiconductors start behaving like at absolute zero temperature?
Suppose white light falls on a double slit but one slit is covered by a violet filter (allowing $\lambda=400\text{nm}$). Describe the nature of the fringe pattern observed.