2018 - WAEC Physics Past Questions and Answers - page 3
Rainbow formation is a natural phenomenon illustrating that white light
splits into three components after rainfall
is dispersed by glass prisms
splits into its constituent colours before rainfall
is dispersed into its constituent colours after rainfall
Rainbows are formed by the dispersion of light and reflection from drops of water in the atmosphere
The lens illustrated above can best be described as a
converging meniscus
plano-convex
diverging meniscus
bi-convex
The diagram is that of a plano-convex lens; which is a type of converging lens.
Two plane mirrors are inclined to each other such that an object placed between them has 11 images. Determine the angle of inclination
30°
45°
60°
90°
Number of images = \(\frac{360}{n} - 1\)
where n is the angle of inclination.
Given the number of images = 11, we have
\(\frac{360}{n} - 1 = 11\)
\(\frac{360}{n} = 12\)
\(n = \frac{360}{12} =30°\)
The pitch of a note is not affected by
When two flat plate conductors are arranged in such a way that they possess equal and opposite charges seperated by a dielectric, they form a/an
Most capacitors contain at least two electrical conductors often in the form of metallic plates or surfaces separated by a dielectric medium.
Which electrical device is illustrated above?
A simple barometer is constructed using a liquid \(Q_{1}\) of density 16.2\(g/cm^{3}\). Calculate the least lenth of the tube to be used to measure pressure of 1.5atm. [Density of mercury = 13.6\(g/cm^{3}\), 1atm = 76.0 cm of Mercury]
Let \(h_{Q}\) and \(\rho_{Q}\) be the least length and the density of \(Q_{1}\)
while \(h\) and \(\rho\) are the length and density of mercury respectively.
\(h\times \rho \times g = h_{Q} \times \rho_{Q} \times g\)
\(76cm \times 13.6 \times 10 = h_{Q} \times 16.2 \times 10\)
\(h_{Q} = \frac{76\times13.6\times10}{16.2\times10}\)
\(h_{Q} = \frac{10336}{162}\)
\(h_{Q} \approxeq 63.8cm = 638mm\)
A bar AB is balanced horizontally on two knife edges as illustrated as in the diagram above. Determine the weight of the bar.
To obtain a virtual, erect and magnified image from a thin converging lens, an object must be placed
When the object is placed between the optical centre of the lens and the focal length, the image formed is virtual, erect and magnified.
The diagram above represents a transverse travelling wave. Which two points are 180° out of phase?