Waec Physics 2012 Past Questions and Answers

Question 16:

• WAEC 2012

A girl stands on a scale in a lift. If the reading on the scale is less than her weight, then the lift is moving

A. Upward at uniform speed
B. Upward with uniform acceleration
C. Downward with uniform speed
D. Downward with uniform acceleration

Question 17:

• WAEC 2012

The S.I unit of heat is

A. Joule
B. Kelvin
C. Watt
D. Ampere

Question 18:

• WAEC 2012

A body is pulled through a distance of 500m by a force of 20N. If the power developed is 0.4kW, calculate the time for which the force acts

A. 250.0s
B. 25.0s
C. 2.5s
D. 0.5s

Question 19:

• WAEC 2012

A metal sheet of area 100cm\(^2\) was heated through 70°C. Calculate its new area if the linear expansivity of the metal is 0.000017K\(^{-1}\).

A. 100.06 cm²
B. 100.12cm²
C. 100.24cm²
D. 100.36cm²

Question 20:

• WAEC 2012

The thermopile is a device for detecting

A. Radioactive radiations
B. Radiant energy
C. X-rays
D. The presence of electrons