Waec Physics 2006 Past Questions and Answers

Question 46:

• WAEC 2006

A 500kV is applied across an X-ray tube. Calculate the maximum velocity of the electrons produced [Me = 9.1 x 10^-31kg, e = 1.6 x 10^-19C]

A. 4.2 x 10⁸ms^-1
B. 1.9 x 10⁸ms^-1
C. 4.2 x 10⁵ms^-1
D. 1.8 x 10⁵ms^-1

Question 47:

• WAEC 2006

A radioactive substance of mass 768g has a half life of 3 years. After how many years does this substance leave only 6g undecayed?

A. 21
B. 18
C. 15
D. 12

Question 48:

• WAEC 2006

Fusion is not usually used for generating electric power because

A. No energy is released when fusion takes place
B. Very high temperatures are required to initiate fusion reaction
C. The raw materials needed is not easily available
D. Heavy nuclei are involved

Question 49:

• WAEC 2006

An atom \(^{234}_{91} P\) emits a gamma radiation. The resultant nuclide is

A. \(^{230}_{90} Th\)
B. \(^{234}_{91} Pa\)
C. \(^{234}_{90} Th\)
D. \(^{234}_{89} Ac\)

Question 50:

• WAEC 2006

The diagram above shows the speed-time graph of a car.If the car covered a total distance of 600m in 25s, calculate its maximum speed

A. 30ms^-1
B. 25ms^-1
C. 20ms^-1
D. 15ms^-1