Question
How much energy is released in the following reaction?$\text{ }^7\text{Li + p}\rightarrow\alpha+\alpha.$
Atomic mass of ${ }^7 \mathrm{Li}=7.0160 \mathrm{u}$ and that of ${ }^4 \mathrm{He}=4.0026 \mathrm{u}$.

Answer

$\text{Li}^7+\text{p}\rightarrow\text{l}+\alpha+\text{E};\text{Li}^7=7.016\text{u}$$\alpha=\text{ }^4\text{He}=4.0026\text{u};\text{p}=1.007276\text{u}$
$\text{E}=\text{Li}^7+\text{P}-2\alpha=(7.016+1.007276)\text{u}\\-(2\times4.0026)\text{u}=0.018076\text{u}.$
$\Rightarrow0.018076\times931=16.828=16.83\text{MeV}.$

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

State Dulong and Petit's law.
The centre of gravity of a body on the earth coincides with its centre of mass for a ‘small’ object whereas for an ‘extended’ object it may not. What is the qualitative meaning of ‘small’ and ‘extended’ in this regard? For which of the following the two coincides? A building, a pond, a lake, a mountain?
An object is to be seen through a simple microscope of focal length 12cm. Where should the object be placed so as to produce maximum angular magnification? The least distance for clear vision is 25cm.
Find the difference in temperature across the surfaces of an iron plate 5 cm thick, through $100 \mathrm{sq} . \mathrm{m}$ of which heat flows at the rate of $9.6 \times 10^5 \mathrm{~J} / \mathrm{s}$. [Take $\mathrm{K}=96 \mathrm{Wm}^{-1} \mathrm{~K}^{-1}$]
A vessel contains 1.60 g of oxygen and 2.80 g of nitrogen. The temperature is maintained at 300 K and the volume of the vessel is $0.166 \mathrm{~m}^3$. Find the pressure of the mixture.
Figure shows a pirateship $560m$ from a fort defending a harbour entrance. A defence cannon, located at sea level, fires balls at initial speed, $u_0 = 82m/ s$.
  1. At what angle, $\theta_0$ from the horizontal must a ball be fired to hit the ship?
  2. What is the maximum range of the cannon balls?
A body of mass 2kg is at rest at a height of 10m above the ground. Calculate its potential energy and kinetic energy after it has fallen through half the height. Also find the velocity at this instant.
A train start moving from rest and its speed increases with uniform acceleration for 10 sec . At the end of 5 sec . its speed become $54 km /$ hour.
(a) Find the acceleration of the train.
(b) What will be its speed after 10 sec ?
(c) How much distance will the train travel in 10 sec?
(d) How much distance did the train cover in the seventh and tenth second respectively?
A long, vertical wire carrying a current of 10A in the upward direction is placed in a region where a horizontal magnetic field of magnitude $2·0 \times 10^{-3}T$ exists from south to north. Find the point where the resultant magnetic field is zero.
Suppose the resistance of the coil in the preivous problem is $25\Omega.$ Assume that the coil moves with uniform velocity during its removal and restoration. Find the thermal energy developed in the coil during:
  1. Its removal.
  2. Its restoration.
  3. Its motion.