Frank solutions for फिज़िक्स पार्ट [अंग्रेजी] कक्षा १० आईसीएसई chapter 6 - Modern Physics [Latest edition]

What do you mean by Atomic number

What do you mean by Mass number.

What do you mean by Atomic mass

State the penetrating range of α, β and γ radiations.

Give the relative ionizing power of α, β and γ radiations.

Which of the radiations α, β and γ is similar to a beam of electrons?

State two similarities and two dissimilarities between the γ-rays and X-rays.

What happens to the position of an element in the periodic table when its nucleus emits an α - particle. Give reason for your answer.

What happens to the position of an element in the periodic table when its nucleus emits β -particle? Give reasons for your answer.

What happens to the position of an element in the periodic table when its nucleus emits γ radiation? Give reason for your answer.

What happens to the atomic number of element when (i) An α -particle, (ii) A β -particle 1 and (iii)  γ-radiation is emitted?

What happens to the mass number of an element when (i) an α -particle, (ii) a β -particle, and (iii) γ -radiation is emitted?

A radioactive source emits three types of radiations. Name them.
(i) Name the radiations which are charged.
(ii) Name the radiations which are most penetrating.
(iii) Name the radiations which travel with the speed of light.
(iv) Name the radiations which have the largest mass.

What kind of change takes place in a nucleus when a β -particle is emitted?

In following fig.  shows a mixed source S of alpha and beta particles in a thick lead container. The particles pass through a magnetic field in a direction perpendicular to the plane of paper (inwards as shown by x). State and show in the diagram how the particles get affected.

In the following  fig. shows a radioactive source S in a thick lead container. The radiations pass through an electric field between the plates P and Q. Complete the diagram to show the paths of α , β and γ radiations.

Why is the source S placed in a thick lead container?

A nucleus of an element X which has the symbol `""_84^202` X emits an alpha particle and then a beta particle. The final nucleus is `""_"b"^"a"` Y Find a and b.

A radioactive nucleus `""_"Z"^"A"` X first emits a beta particle and then an alpha particle to give the resulting nucleus `""_"Q"^"P"` Y  What will be the values of P and Q in terms of A and Z?

Make the correct choices in the following:
(a) In one atom of copper (mass number 63, atomic number 29) there are

A radioactive nuclide `""_86^226` Ra decays by emission of two alpha particles, one beta particle and gamma rays. Which of the following is the resulting nuclide X?

The element X has an atomic mass number of 238 and an atomic number
of 92. It emits an alpha particle forming an element y. Y can be represented
by

An element P has an atomic mass of 239 and an atomic number of 92. It
emits a beta particle forming an element Q. Q can be represented by

Which one of the following statements about alpha and beta particles is
correct?

Define the term radioactivity.

Of the normally occurring radioactive radiation:

Which has a positive charge?

Of the normally occurring radioactive radiation:

Which is most penetrating?

Of the normally occurring radioactive radiation:

Which has no electric charge?

Which of the following statements are correct?
Electrons have

Which of the following statements are correct?

 Neutrons have

Draw a diagram of a simple atom showing the nucleus and electrons. In this atom:
(a) What type of charge will there be on the nucleus?
(b) What is the value of this charge?

One isotopes of uranium has a mass number of 235 and atomic number 92.
(a) What is the number of electrons in a neutral atom of this isotope?

(b) How many protons are there in the nucleus of this isotope?

(c) For another isotope of Uranium state which one of the numbers (238 or 92) changes?

(d) What is the number of protons in ²³⁸U?

Radioactive substances were found to give off three types of rays. Name them. How do they
(a) React to the magnetic field?
(b) React to the electric field?
(c) Act when different thickness of lead sheets is placed in their path?

What is the meaning of mass number?

What do you mean by atomic number?

 In what way are these numbers related to the isotopes of an element?

Explain the use of radioactive in the field of medicine, agriculture and industry.

Distinguish between α, β and γ rays.

What do you understand by radioactive decay? An isotope of Uranium `""_92^238 "U"`  is radioactive and changes into Thorium 92 by the emission of an alpha particle. Write a symbolic equation for this decay process.

The element  `""_11^24 "Na"`  changes to magnesium by the emission of a beta particle. Write down the symbolic equation for the beta emission.

What are the uses of radioactive isotopes in following?
(a) Medical field,
(b) Agriculture,
(c) Industries?