Jamb Physics 2005 Past Questions and Answers

Question 11:

• JAMB 2005

a proton moving with a speed of 1.0 x 10⁶ms^-1 through a magnetic field of 1.0T experiences a magnetic force of magnitude 8.0 x 10^-14 N. The angle between the proton''s velocity and the field is

A. 60°
B. 90°
C. 30°
D. 45°

Question 12:

• JAMB 2005

When impurities are added to semi-conductors, the conductivity of the semi-conductor

A. Increases then decreases
B. Increases
C. Decreases
D. Remains constant

Question 13:

• JAMB 2005

A silicon material is dopped with an element of a certain group and an n-type semi-conductor is formed. the most likely group of the element is

A. V
B. III
C. I
D. II

Question 14:

• JAMB 2005

The charge carriers in gasses are

A. Ions only
B. Electrons and ions
C. Electrons and holes
D. Electrons only

Question 15:

• JAMB 2005

the ray which causes gas molecules to glow is known as

A. Cathode ray
B. Anode ray
C. Molecular ray
D. Gamma ray