Question 421:

• JAMB 1986

The sign of the change on a charged glass rod may be determined with

A. A charged electroscope
B. An uncharged electroscope
C. A galvanometer
D. An electrometer

Question 422:

• JAMB 1986

If the inclination at Ibadan is 7^oS, this means that

A. The angle between the geographic meridian and the magnetic meridian at Ibadan is 7^o
B. The earth's magnetic intensity at Ibadan makes angle 7^o with the horizontal direction
C. A magnetic needle will be inclined at 7^o to the vertical at Ibadan
D. The north pole of a magnetic needle dips downward at Ibadan

Question 423:

• JAMB 1986

The wavelength of ultraviolet radiation is 400nm. If the speed of light in air is 3 x 108ms-1, then the frequency of the ultraviolet radiation is

A. 1.3 x 10¹⁵Hz
B. 7.5 x 10⁵Hz
C. 1.2 x 10¹¹Hz
D. 7.5 x 10¹⁴Hz

Question 424:

• JAMB 1986

Which of the following is most strongly deflected by magnetic field?

A. \(\gamma\) - rays
B. X- particle
C. \(\beta\) - particles
D. X - rays

Question 425:

• JAMB 1986

When a box of mass 45kg, is given an initial speed of 5ms^-1 it slides along a horizontal floor a distance of 3m before coming to a rest. what is the coefficient of kinetic friction between the box and the floor? (G = 10ms^-2)

A. \( \frac{5}{6} \)
B. \( \frac{5}{12} \)
C. \( \frac{1}{3} \)
D. \( \frac{2}{3} \)