Post Utme Physics Past Questions and Answers

Question 1166:

In order to use a converging lens as a magnifying glass, the object must be located atbetween

A. Principal focus and pole
B. Principal focus and centre of curvature
C. Beyond the centre of curvature
D. Principal focus

Question 1167:

What is the critical angle when light passes from a glass of refractive index of \(1.5\) into air?

A. \(41.8^{\circ}\)
B. \(31.8^{\circ}\)
C. \(51.8^{\circ}\)
D. \(35.8^{\circ}\)

Question 1168:

A conducting circular loop of radius \(0.25 m\) is placed in the \(x-y\) plane in a uniform magnetic ficld of \(0.36 T\) and pointing in the positive \(z\)-direction. Calculate the magnetic flux through the loop.

A. \(0.821\) wb
B. \(0.424\) wb
C. \(0.071\) wb
D. \(0.117\) wb

Question 1169:

The ground is always cold at night because the

A. Sun no longer shines at night
B. Atmosphere reflects the sun energy at night
C. Atmosphere absorbs the suns energy at night
D. Earth radiates heat to the atmosphere at night

Question 1170:

Which of the following statements is NOT CORRECT?

A. The induced current is along the same direction
B. The induced current is along the same direction as motion
C. The magnetic flux depends on the magnetic field and the flux area
D. The induced e.m.f is proportional to the rate of magnetic flux