Post Utme Physics Past Questions and Answers

Question 116:

In a resonance tube experiment, a tube of fixed length is closed at one end and several turning forks of increasing frequency used to obtain resonance at the open end. If the turning fork with the lowest frequency which gave resonance had a frequency \(f\) 1and the next turning fork to give resonance had a frequency \(f 2\) find the ratio \(f 2: f 1\)

A. \(1 / 2\)
B. 3
C. 9
D. 8

Question 117:

I. Its velocity is constant
II. No work is done on the body
III. It has constant acceleration directed away from the centre
IV. The centripetal force is directed towards the centre

Which combination above is true of a body moving with constant speed in a circular track?

A. I and III
B. I and IV
C. II and III
D. II and IV

Question 118:

A machine requires \(1000 \mathrm{~J}\) of work to raise a load of \(500 \mathrm{~N}\) through a vertical distance of \(1.5 \mathrm{~m}\). Calculate the efficiency of the machine.

A. \(80 \%\)
B. \(75 \%\)
C. \(\mathrm{SO} \%\)
D. \(33 \%\)

Question 119:

Two forces whose resultant is \(100 \mathrm{~N}\) are at right angles to each other. if one of them makes an angle of \(30^{\circ}\) with the resultant, find the magnitude of the other force.

A. \(8.66 \mathrm{~N}\)
B. \(86.6 \mathrm{~N}\)
C. \(50.0 \mathrm{~N}\)
D. \(5.0 \mathrm{~N}\)

Question 120:

A body of weight \(W N\) rests on a smooth plane inclined at an angle \(\theta^{\circ}\) to the horizontal.
The component of the weight down the slope is ____________

A. \(W \sin \theta\)
B. \(W \cos \theta\)
C. \(W \tan \theta\)
D. \(W \sec \theta\)