Waec Physics 2007 Past Questions and Answers

Question 16:

• WAEC 2007

A plane inclined at 30^o to the horizontal has an efficiency of 50%. Calculate the force parallel to the plane required to push a load of 120N uniformly upn the plane

A. 50.0N
B. 120.0N
C. 200.0N
D. 240N

Question 17:

• WAEC 2007

Mechanical energy can be either

A. Kinetic or electric
B. Chemical or potential
C. Potential or kinetic
D. Electric or heat

Question 18:

• WAEC 2007

Which of the following surfaces will radiate heat energy best?

A. Red surface
B. White surface
C. Black surface
D. Yellow surface

Question 19:

• WAEC 2007

The ice and steam point on a mercury-in-glass thermometer are 10cm and 30cm respectively. Calculate the temperature in decree Celsius when the mercury meniscus is the 14cm mark

A. 20^oC
B. 30^oC
C. 34^oC
D. 70^oC

Question 20:

• WAEC 2007

Which of the following statements distinguishes thermal conduction for convection? i. Conduction requires a material medium while convection does not ii. In convection, there is actual motion of hot material, while in conduction, molecules molecules vibrates faster about their mean positions iii. Conduction takes place in solids while convection takes place in fluids.

A. I and ii only
B. Ii and iii only
C. I and iii only
D. I, ii and iii