Jamb Physics 2012 Past Questions and Answers

Question 56:

• JAMB 2012

The main reason for making the cover of a vacuum flask airtight is to prevent heat loss by

A. Convection
B. Conduction
C. Radiation
D. Evaporation

Question 57:

• JAMB 2012

A radio is operated by eight cells each of e.m.f. 2.0V connected in series. If two of the cells are wrongly connected, the net e.m.f. of the radio is

A. 8V
B. 10V
C. 12V
D. 16V

Question 58:

• JAMB 2012

If a charged ion goes through combined electric and magnetic fields, the resultant emergent velocity of the ion is

A. E/B
B. EB
C. B/E
D. E - B

Question 59:

• JAMB 2012

A projection lantern is used to give the image of a slide on a screen. If the image is 24 times as large as the slide and the screen is 72.0m from the projecting lens, what is the position of the slide from the lens?

A. 0.3m
B. 3.0m
C. 3.5m
D. 4.0m

Question 60:

• JAMB 2012

An electron of charge 1.6 x 10^-19C and mass 9.1 x 10^-31kg is accelerated between two metal plates with a velocity of 4 x 10⁷ms^-1, the potential difference between the plates is

A. 4.55 x 10³V
B. 4.55 x 10²V
C. 9.10 x 10¹V
D. 4.55 x 10¹V