Post Utme Physics Past Questions and Answers

Question 441:

Half-life of a radio active substance is ____________

A. The average life time of the substance
B. The time it takes the substance to decay to half of its original quantity
C. The time it takes the activity of the substance to decay to half of its original value
D. All of the above

Question 442:

The headlamp bulb of a motor car is rated 60 W, 12 V.
Calculate the resistance of its filament ____________

A. 0.2
B. 50
C. 2.4
D. 2 V

Question 443:

In an electrolysis experiment, a cathode of mass 4.5g weighs 4.52 g after a current of 4.5 A flows for 1hour.
The electrochemical equivalent of the deposited substance is ____________

A. 0.00444 g/C
B. 0.00741 g/C
C. 0.00074 g/C
D. 0.00007 g/C

Question 444:

An object falls freely under gravity from a given height. At half way point, its kinetic energy is ____________

A. Exactly half of its initial potential energy
B. Exactly half of its kinetic energy
C. Exactly half of its final potential energy
D. Zero

Question 445:

The silvered walls of a vacuum flask are used to prevent ____________

A. Heat loss due to opacity
B. Heat loss due to radiation
C. Heat loss due to convection
D. Heat loss due to conduction