Physics WAEC - Page 239 of 259

A bar AB is balanced horizontally on two knife edges as illustrated as in the diagram above. Determine the weight of the bar.

A. 10.0N B. 20.0N C. 40.0N D. 50.0N Correct Answer: Option C C. 40.0N

A simple barometer is constructed using a liquid Q1 of density 16.2g/cm³. Calculate the least length of the tube to be used to measure the pressure of 1.5atm. [Density of mercury = 13.6g/cm³, 1atm = 76.0 cm of Mercury]

A. 1358mm B. 957mm C. 760mm D. 638mm Correct Answer: Option D D. 638mm Explanation Let hQ and ρQ be the least length and the density of Q1 while h and ρ are the length and density of mercury respectively. h×ρ×g=hQ×ρQ×g 76cm×13.6×10=hQ×16.2×10 hQ=76×13.6×10/16.2×10...

Which electrical device is illustrated below?

by Sunday | Jan 23 | Physics WAEC

A. a.c. generator B. a.c. motor C. d.c. generator D. d.c. motor Correct Answer: Option C C. d.c. generator

Which of the following electromagnetic waves is most energetic?

by Sunday | Jan 23 | Physics WAEC

A. Radio waves B. X-ray C. Gamma rays D. Ultra-violet rays Correct Answer: Option C C. Gamma rays Explanation The gamma rays have the shortest wavelength and therefore, impart the highest photon energy.