Post Utme Physics Past Questions and Answers

Question 1211:

The force on current carrying conductor in a masnetic field is least when the

A. Conductor makes an angle of \(100^{\circ}\) with the field
B. Force is independent of the angle between the conductor and the field
C. Conductor is parallel with the field
D. Conductor is at right angle with the field

Question 1212:

Two forces \(\vec{A}\) and \(\vec{B}\) act on an object. The angle between the forces is \(60^{\circ}\). The magnitude of \(\vec{A}\) is \(15 N\) while the resultant of the two vectors has a magnitude of \(18 N\). What is the magnitude of vector \(\vec{B}\) ?

A. \(3.00\) N
B. \(4.96\) N
C. \(9.95\) N
D. \(39.9 N\)

Question 1213:

Two forces of magnitudes \(80 N\) and \(60 N\) act on a \(5 kg\) object. If the angle between the two forces is \(120^{\circ}\), the acceleration of the body is ____________

A. \(14.4 m / s ^{2}\)
B. \(20.0 m / s ^{2}\)
C. \(11.9\) \(m / s ^{2}\)
D. \(16.7 m / s ^{2}\)

Question 1214:

A man travelled \(3 km\) due east in 4 mins by bus on a straight road, and then drove a car \(4 km\) due north in 3 mins. Calculate his average velocity.

A. \(0.71 m / s\)
B. \(1.00 m / s\)
C. \(11.9 m / s\)
D. \(16.7 m / s\)

Question 1215:

Force of the same magnitude is applied to each of \(1 kg\) of lead \(( Pb ), 1 kg\) of iron \(( Fe )\) and \(1 kg\) of paper. Which of the three masses has the highest acceleration?

A. Paper
B. Iron
C. Lead
D. All accelerations equal