Question 4856:

Astaresult of air at the top of a barometer the height of the mercury column is \(73.5 cm\) when it should be \(75.0 cm\) the velume of the space above the mereury is \(8.0 cm ^{3}\).
Calculate the correct barometrie height when the barometer reads 74.cm and the volume of the space above the mercury is \(6.0 cm ^{3}\)

A. \(72.0 cm\)
B. \(74.5 cm\)
C. \(75.1 cm\)
D. \(76.0 cm\)

Question 4857:

22,000J of heat is required to raise the temperature of \(1.5 kg\) of paraffin from \(20^{\circ} C\) to \(30^{\circ} C\).
Calculate the specific heat capacity of paraffin:

A. \(14666 jkg ^{-10} C ^{-1}\)
B. \(2933 jkg ^{-10} C ^{-1}\)
C. \(40400 jkg ^{-10} C ^{-1}\)
D. \(5886 jkg { }^{-10} C ^{-1}\)

Question 4858:

An object is placed \(30 cm\) from a concave mirror of focal length \(15 cm\).
the linear magnification of the image produce is ____________

A. O
B. \(2 / 3\)
C. 1
D. 2
E. 3

Question 4859:

An electric cell has an internal resistance of \(20 hm\). A current of \(0.5 A\) is found to flow when a resistor of \(50 hms\) resistance is connected across it.
What is the electromotive force of the cell ____________

A. 5 volts
B. 3.5 volts
C. 2.5 volts
D. 1 volt
E. 10 volt

Question 4860:

A concave lens of focal length \(20 cm\) forms an image \(1 / 2\) the size of the object.
The object distance is ____________

A. \(150 cm\)
B. \(100 cm\)/9
C. \(60 cm\)/7
D. \(60 cm\)
E. None of the above