Post Utme Physics Past Questions and Answers

Question 41:

A force of \(20 \mathrm{~N}\) applied parallel to the surface of horizontal table is just sufficient to make a block of mass \(4 \mathrm{~kg}\) set for motion. Find the acceleration when the force is doubled.

A. \(2 \mathrm{~ms}^{-2}\)
B. \(4 \mathrm{~ms}^{-2}\)
C. \(5 \mathrm{~ms}^{-2}\)
D. \(10 \mathrm{~ms}^{-2}\)

Question 42:

A man walks \(1 \mathrm{~km}\) due east and then \(1 \mathrm{~km}\) due north. His displacement is ____________

A. \(1 \mathrm{~km} N 15^{\circ} \mathrm{E}\)
B. 1 \(\mathrm{km} \mathrm{N} 30^{\circ} \mathrm{E}\)
C. \(\sqrt{2} \mathrm{~km} \mathrm{~N} 45^{\circ} \mathrm{E}\)
D. \(2 \mathrm{~km} \mathrm{~N} 75^{\circ} \mathrm{E}\)

Question 43:

A motor car moves with a velocity of \(20 \mathrm{~ms}^{-1}\) on a rough horizontal road and covers a displacement of \(50 \mathrm{~m}\). Find the coefficient of dynamic friction between the type and the ground \(\left(g=10 \mathrm{~ms}^{-2})\)

A. \(0.3\)
B. \(0.4\)
C. \(0.6\)
D. \(0.5\)

Question 44:

A physics student standing on the edge of a cliff throws a stone vertically downward with an initial speed of \(10.0 \mathrm{~m} / \mathrm{s}\). The instant before the stone hits the ground below, it is traveling at a speed of \(30.0 \mathrm{~m} / \mathrm{s}\). If the physics student were to throw the rock horizontally outward from the cliff instead, with the same initial speed of \(10.0 \mathrm{~m} / \mathrm{s}\), what is the magnitude of the velocity of the stone just before it hits the ground?

A. \(10.0 \mathrm{~m} / \mathrm{s}\)
B. \(20.0 \mathrm{~m} / \mathrm{s}\)
C. \(\quad 30.0 \mathrm{~m} / \mathrm{s}\)
D. \(\quad 40.0 \mathrm{~m} / \mathrm{s}\)

Question 45:

A quantity is defined as the product of cross-sectional area and change in momentum per unit \(C\) length. Which of the following is its SI unit?

A. \(\mathrm{Nm}\)
B. \(\mathrm{kgs}^{-1}\)
C. \(\mathrm{kgm}^{2} \mathrm{~s}^{-1}\)
D. \(\mathrm{Nkgs}^{-1}\)