Physics Past Questions and Answers

A small circular membrane is 10cm below the surface of a pool of mercury when the barometric height is 76 cm of mercury. If the density of mercury is 13600\(kgm^{-3}\), what is the pressure on the membrane in \(Nm^{-2}\)? \((g =10ms^{-2})\)

A 1.17 x 10⁷ Nm^-2
B 6.80 x 10⁵Nm^-2
C 1.17x10⁵Nm^-2
D 1.03 x 10⁵Nm^-2
E 1.36 x10⁴ Nm^-2

Question 257:

Which of the following instruments is used to measure relative humidity?

A Hydrometer
B Barometer
C Manometer
D Hypsometer
E Hygrometer

Question 258:

A metal of mass 1.5 kg was heated from 27^oC to 47^oC in 4 minutes by a boiling ring of 75 W rating. Calculate the specific heat capacity of the metal, (Neglect heat losses to the surrounding)

A 2.5 X10³J kg^-10C^-1
B 6.0 X10²J kg^-10C^-1
C 2.5 x 10²J kg^-10C^-1
D 1.4 X10²J kg^-10C^-1
E 1.0 x 10²J kg^-10C^-1

Question 259:

A ray of light strikes a plane mirror at an angle of incidence i. Determine in terms of i the angle of deviation of the ray after reflection from the mirror.

A I
B 2i
C 90^o-i
D 90^o+ i
E 180^o - 2i

Question 260:

Images formed by a convex mirror are always

A Inverted, real and diminished
B Inverted, virtual and diminished
C Erect, virtual and diminished
D Erect, real and magnified
E Erect, virtual and magnified