Jamb Physics 2009 Past Questions and Answers

Question 31:

• JAMB 2009

Cancerous cells can be destroyed by

A. Ultraviolet rays
B. Alpha particules
C. X - rays
D. Infrared rays

Question 32:

• JAMB 2009

If the decay constant of a radioactive substance is 0.231s¹, the half-life is?

A. 3.00 s
B. 0.12 s
C. 0.33 s
D. 1.50 s

Question 33:

• JAMB 2009

A piece of radioactive material contains 10²⁰ atoms.
If the half life of the material is 20 seconds, the number of disintegration in the first second is

A. 3.47 x 10¹⁸
B. 6.93 x 10 ²⁰
C. 3.47 x 10²⁰
D. 6.93 x 10¹⁸

Question 34:

• JAMB 2009

Thermionic emission is the process whereby

A. β - rays are produced
B. Holes are produced
C. X - rays are produced
D. Electrons leave a hot element

Question 35:

• JAMB 2009

Which of the following can conduct electricity owing to the presence of free mobile electrons?

A. Germanium
B. Silicon
C. Grapefruit
D. Copper