Physics Past Questions and Answers

When th temperature of a liquid is increased, its surface tension

A Increases
B Decreases
C Remain constant
D Increases then decreases

Question 2107:

The distance between an object and its real image in a convex lens is 40cm. If the magnification of the image is 3, calculate the focal length of the lens

A 6.5 cm
B 7.5 cm
C 8.5 cm
D 4.5 cm

Question 2108:

A ray of light passes through the centre of curvature of a concave mirror and strikes the mirror. At what angle is the ray reflected?

A 180\(^o\)
B 90\(^o\)
C 0\(^o\)
D 60\(^o\)

Question 2109:

The pin-hole camera produces a less sharply defined image when the

A Pin-hole is larger
B Illumination is less
C Screen is further from the pin-hole
D Object is further from the pin-hole

Question 2110:

A straight wire 15cm long, carrying a current of 6.0A is in a uniform field of 0.40T. What is the force on the wire when it is at right angle to the field

A 0.46N
B 0.35N
C 0.36N
D 0,24N