POST UTME ABU 2021 Physics | Objective

Practice these randomly selected questions to test your readiness.

Question 1
A 10 Ω resistor is connected in series with a 20 Ω resistor and a 30 Ω resistor. If a voltage of 12 V is applied across the circuit, what is the current flowing through the 10 Ω resistor?
A. 0.4 A
B. 0.6 A
C. 0.8 A
D. 1 A
Question 2
A block of mass $m$ is attached to a horizontal spring with spring cons\tant $k$. If the block is displaced by a dis\tance $x$ from its equilibrium position and released, what is the maximum speed of the block?
A. \sqrt{\frac{kx^2}{m}}
B. \sqrt{\frac{mx^2}{k}}
C. \sqrt{\frac{k}{m}}
D. \sqrt{\frac{m}{k}}
Question 3
A ray of light passes from air into a glass slab of re\fractive index 1.5. If the angle of incidence is 30°, calculate the angle of re\fraction.
A. 20°
B. 25°
C. 30°
D. 35°
Question 4
A particle of mass 1 kg is moving in a circular path of radius 2 m with a cons\tant speed of 4 m/s. Calculate the magnitude of the force acting on the particle.
A. 10 N
B. 20 N
C. 30 N
D. 40 N
Question 5
A spring with a force cons\tant of 200 N/m is stretched by 0.1 m. Calculate the work done in stretching the spring.
A. 2 J
B. 4 J
C. 6 J
D. 8 J
Question 6
A radioactive sample has a half-life of $10$ years. If the initial activity is $100\,Bq$, what is the activity after $20$ years?
A. 12.5\,Bq
B. 25\,Bq
C. 50\,Bq
D. 100\,Bq
Question 7
A circuit consists of a resistor $R$, an inductor $L$, and a capacitor $C$ connected in series. If the circuit is driven by an AC voltage source with frequency $f$, what is the impedance of the circuit?
A. \sqrt{R^2 + \( \omega L - \frac{1}{\omega C} \)^2}
B. \sqrt{R^2 + \( \omega L + \frac{1}{\omega C} \)^2}
C. \sqrt{R^2 + \( \omega L - \frac{1}{\omega C} \)^2}
D. \sqrt{R^2 + \( \omega L + \frac{1}{\omega C} \)^2}
Question 8
A parallel-plate capacitor has plates of area $A$ and separation $d$. If a charge $Q$ is placed on one plate, what is the electric field between the plates?
A. \frac{Q}{\epsilon_0A}
B. \frac{Q}{\epsilon_0d}
C. \frac{Q}{\epsilon_0A^2}
D. \frac{Q}{\epsilon_0d^2}
Question 9
A photon of energy 2 eV is incident on a metal surface. If the work function of the metal is 1.5 eV, what is the maximum kinetic energy of the emitted electron?
A. 0.5 eV
B. 1 eV
C. 1.5 eV
D. 2 eV
Question 10
A particle of mass $m$ is moving in a circular path of radius $r$ with a cons\tant speed $v$. The particle experiences a centripetal force $F_c$ given by $F_c = \frac{mv^2}{r}$. If the particle's speed is doubled to $2v$, what is the new centripetal force $F_{c,new}$?
A. \frac{2mv^2}{r}
B. \frac{mv^2}{2r}
C. \frac{mv^2}{r}
D. \frac{mv^2}{4r}
Question 11
A fluid of density $\rho$ is flowing through a pipe of radius $R$ with a velocity $v$. If the velocity is doubled, what happens to the volume flow rate?
A. The volume flow rate remains the same.
B. The volume flow rate increases by a factor of 2.
C. The volume flow rate increases by a factor of 4.
D. The volume flow rate decreases by a factor of 2.
Question 12
A particle of mass 2 kg is moving in a circular path with a radius of 3 m. If the particle's speed is 4 m/s, what is the magnitude of the centripetal acceleration?
A. 2 m/s^2
B. 4 m/s^2
C. 6 m/s^2
D. 8 m/s^2
Question 13
A capacitor consists of two parallel plates separated by a dis\tance of 2 mm. If the capaci\tance is 10 μF, what is the charge stored on the capacitor when a potential difference of 5 V is applied?
A. 50 μC
B. 100 μC
C. 200 μC
D. 500 μC
Question 14
A light ray passes through a prism with apex angle $\theta$ and is re\fracted at an angle $\phi$ to the normal. If the angle of incidence is $\alpha$, what is the angle of re\fraction?
A. \alpha - \phi
B. \alpha + \phi
C. \alpha - \theta
D. \alpha + \theta
Question 15
A particle of mass $m$ is moving in a circular orbit of radius $r$ with speed $v$. If the particle is subject to a centripetal force $F_c = \frac{mv^2}{r}$, what is the magnitude of the acceleration of the particle?
A. \frac{v^2}{r}
B. \frac{mv^2}{r^2}
C. \frac{mv^2}{r}
D. \frac{v^2}{r^2}

Master the Exam!

You've seen a preview, but there are thousands more questions plus AI tutor to break down complex solutions.

Unlock Full Access Available for Android & Windows
Help others prepare! Share this practice hub: