Post Utme Physics Past Questions and Answers

Question 166:

Two points on a velocity-time graph have coordinates \((55\), \(10 \mathrm{~m} / \mathrm{s})\) and \((20 \mathrm{~s}, 20 \mathrm{~m} / \mathrm{s})\). Calculate the mean acceleration between the two points.

A. \(0.67 \mathrm{~m} / \mathrm{s}^{2}\)
B. \(0.80 \mathrm{~m} / \mathrm{s}^{2}\)
C. \(1.50 \mathrm{~m} / \mathrm{s}^{2}\)
D. \(2.00 \mathrm{~m} / \mathrm{s}^{2}\)

Question 167:

Which of the following statements are correct?
i. Land and sea-breezes are natural convection
ii: The vacuum in a thermos flask prevents heat to due to convection anly
iii. Convection may occur in liquids or gases but in solids

A. I and ii only
B. Ii arid- iii only
C. I and iii only
D. I, ii and iii only

Question 168:

The property of the eye known as its power of accommodation it controlled by the ____________

A. Pupil
B. Vitreous humour
C. Iris
D. Ciliary muscles

Question 169:

Under constant tension and constant mass per unit length, the note produced by a plucked string is \(500 \mathrm{~Hz}\) when the-length of the wire is \(0.9 \mathrm{~m}\). At what length is the frequency \(150 \mathrm{~Hz}\) ?

A. \(3 m\)
B. \(0.27 \mathrm{~m}\)
C. \(8.33 \mathrm{~m}\)
D. \(6740 \mathrm{~m}\)

Question 170:

An object is placed in front of two plain mirrors inclined at an angle of \(\theta^{\circ}\). If the total number of images formed is 7 , find the value of \(\theta^{\circ}\)

A. \(30^{\circ}\)
B. \(45^{\circ}\)
C. \(517^{\circ}\)
D. \(90^{\circ}\)