POST UTME MOUNTAIN TOP UNIVERSITY 2020 Physics | Objective

Practice these randomly selected questions to test your readiness.

Question 1
A parallel plate capacitor has a capaci\tance of 10 μF. If a potential difference of 20 V is applied across it, what is the charge stored?
A. 200 μC
B. 2000 μC
C. 20000 μC
D. 200000 μC
Question 2
A heat engine operates between two temperatures $T_1$ and $T_2$. If the efficiency of the engine is $\eta = 1 - \frac{T_2}{T_1}$, find the temperature of the hot reservoir in terms of the efficiency and the temperature of the cold reservoir.
A. \frac{T_2}{T_1} = 1 - \eta
B. \frac{T_2}{T_1} = \eta - 1
C. \frac{T_2}{T_1} = \frac{\eta}{1 - \eta}
D. \frac{T_2}{T_1} = \frac{1 - \eta}{\eta}
Question 3
A circuit consists of a 10 Ω resistor, a 20 Ω resistor, and a 5 Ω resistor connected in series. If a voltage of 12 V is applied across the circuit, what is the current through the 5 Ω resistor?
A. 0.5 A
B. 1.0 A
C. 1.5 A
D. 2.0 A
Question 4
A light ray passes through a prism of angle A and is re\fracted at an angle θ. If the angle of incidence is i, what is the angle of re\fraction?
A. \sin A \cos \theta
B. \sin A \cos \theta - \sin \theta \cos A
C. \sin A \cos \theta - \sin \theta \sqrt{1 - \sin^2 A}
D. \sin A \cos \theta + \sin \theta \cos A
Question 5
A light ray passes through a prism and is re\fracted. If the angle of incidence is $30^\circ$ and the angle of re\fraction is $20^\circ$, find the angle of deviation.
A. \theta_d = \theta_i - \theta_r
B. \theta_d = \theta_i + \theta_r
C. \theta_d = \theta_i - \theta_r + \theta_r
D. \theta_d = \theta_i + \theta_r - \theta_r
Question 6
A beam of light is incident on a glass slab at an angle of incidence of 45°. If the re\fractive index of glass is 1.5, calculate the angle of re\fraction.
A. 30°
B. 45°
C. 60°
D. 75°
Question 7
A particle of mass 2 kg is moving in a circular path of radius 3 m with a cons\tant speed of 4 m/s. What is the magnitude of the force acting on the particle?
A. 8 N
B. 12 N
C. 16 N
D. 20 N
Question 8
A vector $\vec{a}$ is given by $\vec{a} = \begin{pmatrix} 2 \ 3 \ 4 \end{pmatrix}$. Find the magnitude of the vector.
A. \|\vec{a}\| = \sqrt{2^2 + 3^2 + 4^2}
B. \|\vec{a}\| = \sqrt{2^2 + 3^2 - 4^2}
C. \|\vec{a}\| = \sqrt{2^2 - 3^2 + 4^2}
D. \|\vec{a}\| = \sqrt{2^2 - 3^2 - 4^2}
Question 9
A radioactive sample decays from 100 g to 50 g in 5 years. What is the half-life of the sample?
A. 2 years
B. 3 years
C. 5 years
D. 10 years
Question 10
A thermodynamic system undergoes a process from state A to state B, where the initial temperature is 300 K and the final temperature is 400 K. If the specific heat capacity of the system is 1000 J/kg·K, what is the change in internal energy?
A. 40000 J
B. 50000 J
C. 60000 J
D. 70000 J
Question 11
A particle of mass m is in a one-dimensional potential well of depth V0. If the particle's energy is E, what is the probability of finding the particle in the region x > 0?
A. 1/2
B. 1/4
C. 1/3
D. 1/6
Question 12
A charged particle of mass m and charge q is moving in a magnetic field of strength B. If the particle has a velocity v, what is the magnitude of the force exerted on the particle?
A. qvB
B. 2qvB
C. 3qvB
D. 4qvB
Question 13
A block of mass 5 kg is placed on a horizontal, frictionless surface. A horizontal force of 10 N is applied to the block, cau\sing it to accelerate. What is the acceleration of the block?
A. 0.5 m/s^2
B. 1 m/s^2
C. 2 m/s^2
D. 5 m/s^2
Question 14
A solid sphere of radius R is made of a material with Young's modulus Y. If a force F is applied \tangentially to the sphere's surface, the resulting displacement is given by the equation \( delta = \frac{FR}{4pi Yr^3} \). What is the value of the cons\tant r?
A. R
B. 2R
C. R/2
D. R/3
Question 15
A gas is enclosed in a cylinder with a movable piston. The gas is heated, cau\sing its pressure to increase. If the piston is allowed to move freely, what will happen to the volume of the gas?
A. The volume of the gas will decrease.
B. The volume of the gas will increase.
C. The volume of the gas will remain cons\tant.
D. The volume of the gas will increase and then decrease.

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: