Class10th Physics Chapter 18


Total Marks: 30

1. the proton heavier than an electron?
1836times 1863 times 1870 times 1800 times
2. isotopes of hydrogen are :
2 3 4 5
3. The central part of an atom is called ?
Electron Proton Nucleus Neutrons
4. the nucleus of an atom consists of
Protons and Newtrans Neutrons Proton none of these
5. The particles which revolves round the nucleus is called
Proton Neutrons Electron none of these
6. During natural radioactivity how many types of radiations are emitied
1 2 3 4
7. Radioactivity is a process in which certain elements naturally emit radiation with a larger charge number?
86 82 80 92
8. Radio activity is ?
Automated processes continuous process irrreversable processes All
9. Which of the following elements is not radioactive?
Uranium Polonium Thorium Sodium
10. Which of the following elements is radioactive?
Uranium Plutenium Radium All of these
11. Atomic number can be found by what relation ?
Z+A A - N A+N Z-A
12. alpha rays consist of particals which have
Positive charge Negative charge No charge None of these
13. How many distances can be covered in the particles emitted from uranium?
8.62cm 8.61cm 8.64cm 2.7cm
14. by nature gamma rays are :
Positively charged radiation Negative charge reduction Electromagnetic radiation Magnetic radiation
15. For the dignosis tumor is used
Carbon 14 Cobalt 32 Phosphorus 60 Iodine 131
16. The half life of carbon in years is :
7530 year 5730 year 5370 year 3750 year
17. The isototpes of iodine 131 is used in the treatment of :
blood cancer bone cancer lungs cancer thyroid cancer
18. The half life of hydrogen is :
12.3 years 5730 years 30 year 2.85 years
19. The half-life of plutonium is years
3.85 2.85 1.85 0.85
20. safe limit of radiation exposure in one year is :
4rem 5rem 3rem 6rem
21. It can usually be replaced by a shower of ------ in a more settled element:
92 82 90 80
22. What happens to the atomic number of an element which emits one alpha particle and a beta particle ?
Increases by 1 Stays the same Decreases by 2 Decreases by 1
23. The half–life of a certain isotope is 1 day. What is the quantity of the isotope after 2 days.
One half One quarter One eighth Zero
24. By the process, when a heavy nucleus splits into two smaller nuclei.
Nuclear energy will be released Chemical energy will be released Nuclear energy will be absorbed Chemical energy will be absorbed
25. The half life of cobalt is.
40 years 50 years 20 years 30 years
26. Half life of iodine I is.13153
10.5 days 8.07 days 12.5 days 16.9 days
27. The smallest part of an element is called?
Atom Proton Neutron Electron
28. The reason carbon-dating works is that
Plants and animals are such strong emitters of carbon-14 After a plant or animal dies, it stops taking in fresh carbon-14 There is so much non- radioactive carbon dioxide in the air When a plant or an animal dies it takes in fresh carbon
29. When a heavy nucleus splits into two lighter nuclei, the process would
Release nuclear energy Absorb energy Release chemical energy Absorb chemical energy
30. Release of energy by the Sun is due to
Nuclear fission Nuclear fusion Burning of gases Chemical reaction