Post Utme Physics Past Questions and Answers

Question 1226:

\(6000 J\) of heat is delivered to \(10 g\) of dry ice at \(0^{\circ} C\). What is the final temperature if the container has a heat capacity of \(20 J / k\) ? [specific heat of water \(=4200 J / kg . k\), latent heat of fusion of ice ____________
\(\left.=3.33 \times 10^{5} J / kg \right]

A. \(142 .9^{\circ} C\)
B. \(63.6^{\circ} C\)
C. 43. \(0^{\circ} C\)
D. \(0^{\circ} C\)

Question 1227:

A sample of radioactive substance, whose half - life is 16 days, registers 32 decays per second. How long will it take for the rate of decay to reduce to 2 decays per second?

A. 80 days
B. 64 days
C. 48 days
D. 32 days

Question 1228:

When white light passes through a triangular prism, the emerging rays of light arranged in order of decreasing angle of deviation are ____________

A. Red, orange, yellow, green
B. Blue, green, orange, yellow
C. Red, green, yellow, blue
D. Blue, green, yellow, orange

Question 1229:

The electric field between two parallel plates is E. A particle of mass \(m\) and carrying charge \(q\) is released at a point half the distance between the plates. The velocity of the particle \(t\) seconds after its release is ____________

A. \(q E t / m\)
B. \(q E R / 2 m\)
C. \(m q R / 2 E\)
D. \(m q t / 2 E\)

Question 1230:

The velocity of a \(500 kg\) car moving along a straight road, changes from \(12 m / s\) to \(20 m / s\) in \(5 sec\). Calculate the average force moving the car

A. \(2000 N\)
B. \(1600 N\)
C. \(1200 N\)
D. \(800 N\)