Question Library
Browse, filter, and study verified past examination questions with step-by-step mathematical reasoning.
Searching 18,000+ Questions...
Sifting topics, KaTeX formulas & verified solutions
Showing 871–885 of 1023 verified questions
Sort by:
Physics
UTME / JAMB 1990
Heat Energy & Temperature
Which of the following is a vector?
A
Electric charge
B
Electric field
C
Electrical potential difference
D
Electrical capacitance
medium Difficulty
Verified Correct Answer: Option B
Physical Principles & Numerical Solution
No expanded working has been attached for this question yet. The verified answer is Option B.
Source: Myschool Past Questions Archive (Record #28275)
Physics
UTME / JAMB 1990
Heat Energy & Temperature
Solution
When a known standard resistor of 2\(\Omega\) is connected to the 0.0cm end of a meter bridge, the balance point is found to be at 55.0cm. What is the value of the unknown resistor?
A
1.10\(\Omega\)
B
1.64\(\Omega\)
C
2.44\(\Omega\)
D
27.50\(\Omega\)
medium Difficulty
Verified Correct Answer: Option B
Physical Principles & Numerical Solution
\(\frac{R_1}{R_2}\) = \(\frac{L_1}{R_2}\)
\(\frac{2}{R_2}\) = \(\frac{55}{45}\)
R = 1.64\(\Omega\)
Source: Myschool Past Questions Archive (Record #28279)
Physics
UTME / JAMB 1990
Heat Energy & Temperature
Which of the following is an essential physical property of the wires used for making fuses?
A
low density
B
high thermal conductivity
C
low electrical resistivity
D
low melting point
medium Difficulty
Verified Correct Answer: Option D
Physical Principles & Numerical Solution
No expanded working has been attached for this question yet. The verified answer is Option D.
Source: Myschool Past Questions Archive (Record #28285)
Physics
UTME / JAMB 1990
Heat Energy & Temperature
Solution
A substance has a half of 3mins. after 6mins. the count rate was observed to be 400. What was its count rate at zero time?
A
200
B
1200
C
1600
D
2400
medium Difficulty
Verified Correct Answer: Option C
Physical Principles & Numerical Solution
Let the count rate at zero time be K
Count rate after 3mins, = \(\frac{K}{2}\)
Count rate after 6mins = \(\frac{K}{4}\)
but count after 6mins = 400 ( given )
Then = \(\frac{K}{4}\) = 400
K = 4 X 400 = 1600
∴ = count rate at zero time = 1600.
Source: Myschool Past Questions Archive (Record #28301)
Physics
UTME / JAMB 1990
Heat Energy & Temperature
Solution
A force of 5N act at a point Y on a rod XYZ as shown in the diagram above, if XY is 2m. What is the moment of the force about point X?
A
0Nm
B
3Nm
C
7Nm
D
10Nm
E
reflection and diffraction
medium Difficulty
Verified Correct Answer: Option A
Physical Principles & Numerical Solution
X is in the line of action of the force, Therefore moment is equal to zero.
Moment = force x perpendicular distance. ( x is horizontal distance, not perpendicular distance)
Source: Official Exam / Past Question Archive
Physics
UTME / JAMB 1990
Heat Energy & Temperature
Diagram
What is the reading of the vernier scale above
Attached Figure / Diagram
A
1.88cm
B
1.80cm
C
1.28cm
D
1.97cm
medium Difficulty
Verified Correct Answer: Option A
Physical Principles & Numerical Solution
No expanded working has been attached for this question yet. The verified answer is Option A.
Source: Myschool Past Questions Archive (Record #41692)
Physics
WAEC / WASSCE 1989
Heat Energy & Temperature
Which of the following is NOT a vector quantity?
A
momentum
B
force
C
velocity
D
temperature
E
displacement
medium Difficulty
Verified Correct Answer: Option D
Physical Principles & Numerical Solution
No expanded working has been attached for this question yet. The verified answer is Option D.
Source: Myschool Past Questions Archive (Record #23852)
Physics
WAEC / WASSCE 1989
Heat Energy & Temperature
Which of the following is a derived unit?
A
Metre
B
Coulomb
C
Kilogram
D
Second
E
Ampere
medium Difficulty
Verified Correct Answer: Option B
Physical Principles & Numerical Solution
No expanded working has been attached for this question yet. The verified answer is Option B.
Source: Myschool Past Questions Archive (Record #23894)
Physics
WAEC / WASSCE 1989
Heat Energy & Temperature
Solution
Which of the following statements is/are not correct?
A
Evaporation takes place only at the surface of the liquid
B
Boiling takes place throughout the volume of the liquid
C
Evaportaion takes place at all temperatures
D
Boiling takes place at a particular temperature for a liquid at a fixed external pressure
E
The boiling point of a liquid is not affected by impurities
medium Difficulty
Verified Correct Answer: Option E
Physical Principles & Numerical Solution
The boiling point of a liquid is not affected by impurities
Source: Myschool Past Questions Archive (Record #23909)
Physics
WAEC / WASSCE 1989
Heat Energy & Temperature
A short chain is usual attached to the back of a petrol tanker trailing behind it to ensure that the
A
petrol tanker is balanced on the wh eel
B
heat generated by friction in the engine can be conducted to the floor
C
charges generated by friction in the tanker can be conducted to the earth
D
the tanker moves slowly as the chain touches the floor
E
chain produces sound for the resonance of the tanker engine
medium Difficulty
Verified Correct Answer: Option C
Physical Principles & Numerical Solution
No expanded working has been attached for this question yet. The verified answer is Option C.
Source: Myschool Past Questions Archive (Record #23916)
Physics
WAEC / WASSCE 1989
Heat Energy & Temperature
The image in a pine-hole camera is always
A
diminished
B
enlarged
C
upright
D
inverted
E
blurred
medium Difficulty
Verified Correct Answer: Option D
Physical Principles & Numerical Solution
No expanded working has been attached for this question yet. The verified answer is Option D.
Source: Myschool Past Questions Archive (Record #23918)
Physics
WAEC / WASSCE 1989
Heat Energy & Temperature
Solution
What is the gravitational potential due to a molecule of mass, m and at a distance, r from it? (G = gravitational constant).
A
Gm2/r2
B
Gm/r
C
Gm2/r
D
G2m2/r
E
m2/Gr2
medium Difficulty
Verified Correct Answer: Option B
Physical Principles & Numerical Solution
The gravitational potential (often denoted as V or φ) due to a single point mass m (such as a molecule treated as a point mass) at a distance r from it is given by:
V = - \(\frac{\text{G m}}{\text{r}}\)
Where: G is the gravitational constant, m is the mass of the molecule, r is the distance from the center of the molecule to the point where the potential is being evaluated. The negative sign is conventional: gravitational potential is zero at infinity and becomes more negative (lower) as you get closer to the mass.
Source: Myschool Past Questions Archive (Record #23926)
Physics
WAEC / WASSCE 1989
Heat Energy & Temperature
Solution
(a)(i) Explain the terms: photoelectric emission and threshold frequency; (ii) Einstein's photoelectric equation can be written as \(E = hf - hf_{o}\) What does each of the symbols used in the equation above represent?
(b) Calculate the frequency of the proton whose energy is required to eject a surface electron with a kinetic energy of \(1.97 \times 10^{-16} eV\) if the work function of the metal is \(1.33 \times 10^{-16}eV\). \((1 eV = 1.6 \times 10^{-18}J; h = 6.60 \times 10^{-34}JS)\).
(c) In a photoelectric cell, no electrons are emitted until the threshold frequency of light is reached. Explain what happens to the energy of the light before emission of electrons begins. State one factor that may affect the numbers of emitted electrons.
(d) Explain what is meant by the duality of matter, illustrating your answer with observation phenomena.
A
q2/4πεr
B
rε0/q2
C
4πq/ε0
D
qr2/ε0
E
\(\frac{q^2}{4\piεor^2}\)
medium Difficulty
Verified Correct Answer: Option E
Physical Principles & Numerical Solution
a(i) Photoelectric emission occurs when electrons are emitted from the surface of metal plate when it is illuminated by light of sufficient high frequency. Threshold frequency is the minimum frequency of the illuminating light which will just be sufficient to cause photoelectric emission. Below this frequency, electrons will not be emitted.
(ii) In the Einstein's photoelectric equation \(E = hf - hf_{0}\),
E - is the maximum kinetic energy of the emitted electron ;
hf - is the energy of the illuminating light;
\(hf_{0}\) - is the work function. It represents the minimum energy required to liberate electrons from the surface of the metal
\(f_{0}\) - is the threshold frequency.
(b) Using \(E = hf - hf_{0}\)
\(f = \frac{E + hf_{0}}{h}\)
(d) The duality of matter means that matter can exhibit wave properties as well as have particle properties. This double nature of matter is general in nature e.g. particles like electrons can have wave properties. Waves such as X-rays can have particle properties. This is equally illustrated by photoelectric effect.
De Broglie equation for the waves carried with particle is
\(\lambda = \frac{h}{mv} = \frac{h}{p}\)
mv = p is momentum of particle of mass m; h - planks constant.
Source: Official Exam / Past Question Archive
Physics
UTME / JAMB 1989
Heat Energy & Temperature
Which of the following is a set of vectors?
A
force, mass and moment
B
acceleration, velocity and moment
C
mass, weight and density
D
mass, volume and density
medium Difficulty
Verified Correct Answer: Option B
Physical Principles & Numerical Solution
No expanded working has been attached for this question yet. The verified answer is Option B.
Source: Myschool Past Questions Archive (Record #28304)
Physics
UTME / JAMB 1989
Heat Energy & Temperature
Solution
A column of air 10.0cm long is trapped in a tube at 27oC. What is the length of the volume at 100oC?
A
12.4cm
B
13.7cm
C
18.5cm
D
37.0cm
medium Difficulty
Verified Correct Answer: Option A
Physical Principles & Numerical Solution
\(\frac{V_1}{T_1}\) = \(\frac{V_2}{T_2}\)
\(\frac{10\times A}{27 + 273}\) = \(\frac{L\times A}{100 + 273}\)
L = 12.43cm
Source: Myschool Past Questions Archive (Record #28329)