Post Utme Physics Past Questions and Answers

Question 1076:

An object is $5cm$ away from the pole of a convex lens whose radius of curvature is $30cm$. What is the nature of the object's image?

A. Real and magnified
B. Real and diminished
C. Virtual and magnified
D. Virtual and diminished

Question 1077:

When white light passes through a glass prism, the colours of light coming out arranged in the order of decreasing angle of deviation are ____________

A. Red, orange, yellow
B. Violet, green, red
C. Yellow, red, blue
D. Blue, orange, green

Question 1078:

A man standing at some distance from a sharp cliff, hears the echo of his clap $1.2$ seconds after he claps. How far from the cliff is the man?
The speed of sound in air is $340m/s$

A. $283.3m$
B. $204.0m$
C. $408.0m$
D. $566.7m$

Question 1079:

Both proton and electron carry charges whose magnitude equals $1.6\times {10}^{-19}$. Calculate the electrostatic potential between the electron and the proton in a hydrogen atom when the separation between them is $0.5\times {10}^{-10}m$. $[{\epsilon }_0=$ $8.85\times {10}^{-12}N\cdot m^2/C^2]$

A. $1.84\times {10}^{3}J$
B. $2.1\times {10}^{-7}J$
C. $9.2$ $\times {10}^{-8J}$
D. $4.6\times {10}^{-18J}$

Question 1080:

A uniform magnetic field lies in the positive $x$-direction. An electron moving in the negative $y$-direction enters the region of the magnetic field. Which of the following statements is true about the direction of motion of the electron?

A. Electron moves in a circle whose plane is parallel to the $x-y$ plane
B. Electron moves in a circle whose plane is parallel to the $y-z$ plane
C. Electron moves faster in the negative $y$-direction
D. Electron changes direction and begins to move in the positive $x$-direction