175- In a hydraulic lift where the pistons are in equilibrium and the fluid is level, the diameter of the large piston is 10 times the diameter of the small piston. The pressure under the large piston is how many times the pressure under the small piston?
\begin{flushright} (1) $100$ (2) $10$ (3) $5$ (4) $1$ \end{flushright}

176- In the figure, two containers of equal depth are filled with water. If horizontal forces are applied to the surfaces of the containers, $F_1$ and $F_2$ are the forces on the bottoms of containers (1) and (2) respectively, and $P_1$ and $P_2$ are the water pressures at the bottoms. Which relationship is correct? (The masses of the containers are equal.)
[Figure: Two containers, container (2) with base radius $r$ (wider at top, narrower at bottom) and container (1) with base radius $2r$ (narrower at top, wider at bottom)]
\begin{flushright} (1) $P_1 = \dfrac{1}{4}P_2$ and $F_1 = F_2$
(2) $P_1 = P_2$ and $F_1 = 4F_2$
(3) $P_1 = P_2$ and $F_1 = F_2$
(4) $P_1 = 4P_2$ and $F_1 = \dfrac{1}{4}F_2$ \end{flushright}

177- A graduated cylinder contains water. We drop a 42-gram ball into it, and the water level rises from $50\ \text{cm}^3$ at $5^\circ$ to $54\ \text{cm}^3$. What is the density of the ball in grams per cubic centimeter?
\begin{flushright} (1) $3.5$ (2) $10.5$ (3) $21$ (4) $42$ \end{flushright}
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178. Three point charges are placed according to the figure below. The magnitude of the electric field at point M is how many newtons per coulomb?
$$\left(K = 9\times10^9 \,\frac{\text{N.m}^2}{\text{C}^2}\right)$$
[Figure: Point M is located 6 cm above the midpoint of a horizontal line. $q_1 = 12.5\,\mu\text{C}$ is on the left end, $q_2 = -12.5\,\mu\text{C}$ is on the right end, each 8 cm from the center, and $q_3 = 7.2\,\mu\text{C}$ is at the bottom center.]

• [(1)] $18\sqrt{2}\times10^6$
• [(2)] $6\sqrt{2}\times10^6$
• [(3)] $6\times10^6$
• [(4)] $18\times10^6$

179. In a circuit, the energy stored in each capacitor is equal. What is the relationship between the capacitances?
[Figure: Circuit with three capacitors $C_1$, $C_2$, $C_3$ connected to voltage source $V$. $C_1$ and $C_3$ are in series with each other, and $C_2$ is in parallel with that series combination.]

• [(1)] $C_1 = C_2 = \dfrac{1}{4}C_3$
• [(2)] $C_1 = C_2 = 4C_3$
• [(3)] $C_1 = C_2 = \dfrac{1}{2}C_3$
• [(4)] $C_1 = C_2 = 2C_3$

180. In the figure, what are A, B, and C respectively?
[Figure: A light bulb with parts labeled A (bottom), B (middle), and C (top).]

• [(1)] Insulator (glass base), mixture of hydrogen and oxygen
• [(2)] Insulator (glass base), mixture of argon and nitrogen
• [(3)] Metal contact points (base), mixture of hydrogen and oxygen
• [(4)] Metal contact points (base), mixture of argon and nitrogen

181. The figure shows part of an electric circuit. In this circuit, which is in steady state, what is $V_A - V_C$ in volts?
[Figure: Circuit with: from A, resistor $R_1 = 4\,\Omega$, then battery $\varepsilon_1 = 6\,\text{V}$ with internal resistance $r_1 = 1\,\Omega$, then resistor $R_2 = 3\,\Omega$, then a node with current $1\,\text{A}$ going right through $R_3 = 2\,\Omega$ to point C; capacitor $C = 6\,\mu\text{F}$ connected at the node; battery $\varepsilon_2 = 3\,\text{V}$ with internal resistance $r_2 = 2\,\Omega$ connected at point B below.]

• [(1)] $6$
• [(2)] $9$
• [(3)] $12$
• [(4)] $16$

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182. In the circuit shown, how many amperes is $I'$?
[Figure: Circuit with $6\,\Omega$, $3\,\Omega$, $2\,\Omega$ resistors in series, battery $\varepsilon = 36\,\text{V}$, internal resistance $r = 2\,\Omega$, and current $I'$ through the branch]

• [(1)] zero
• [(2)] $0.5$
• [(3)] $2.5$
• [(4)] $1.5$

183. In the circuit shown, the voltage across capacitor $C_1$ is how many times the voltage across capacitor $C_2$?
[Figure: Circuit with $4\,\Omega$ resistor, $2\,\Omega$ resistor, $C_1 = 6\,\mu\text{F}$, $5\,\Omega$ resistor, $C_2 = 4\,\mu\text{F}$, battery $\varepsilon = 20\,\text{V}$, internal resistance $r = 1\,\Omega$]

• [(1)] $\dfrac{2}{3}$
• [(2)] $\dfrac{3}{2}$
• [(3)] $\dfrac{4}{5}$
• [(4)] $\dfrac{5}{4}$

184. A particle with mass $500\,\text{mg}$ enters a uniform magnetic field of $4\,\text{mT}$ perpendicularly at a speed of $10^3\,\dfrac{\text{m}}{\text{s}}$. If the electric charge of the particle is $50\,\mu\text{C}$, what is the acceleration of the particle under the influence of the field, in meters per second squared?

• [(1)] $0.40$
• [(2)] $0.04$
• [(3)] $0.20$
• [(4)] $0.02$

185. A long straight wire carries a current of $20\,\text{A}$. The magnetic field at a distance of $10\,\text{cm}$ from this wire is how many gauss? $$\left(\mu_\circ = 4\pi \times 10^{-7}\,\frac{\text{T.m}}{\text{A}}\right)$$

• [(1)] $4\times10^{-3}$
• [(2)] $4\times10^{-1}$
• [(3)] $4\pi\times10^{-5}$
• [(4)] $4\pi\times10^{-2}$

186. The mutual inductance of a solenoid is $0.05\,\text{H}$ and the electric current passing through it in SI is given by $I = 0.4\sin(500\pi t)$. What is the magnitude of the induced EMF in the solenoid at the moment $t = 0.1\,\text{s}$, in volts?

• [(1)] $1.57$
• [(2)] $3.14$
• [(3)] $15.7$
• [(4)] $31.4$

187. If the magnetic field vector in SI is $\vec{B} = 0.3\,\hat{i} + 0.4\,\hat{j}$ and a loop with area $200\,\text{cm}^2$ lies parallel to the $xz$-plane and perpendicular to the $y$-axis in this field, what are the magnitude of the magnetic field, the magnetic flux through the loop, and the direction of the magnetic flux passing through the loop from right to left in SI, respectively?

• [(1)] zero, zero
• [(2)] $6\times10^{-3}$,\ $0.5$
• [(3)] $8\times10^{-3}$,\ $0.7$
• [(4)] $8\times10^{-3}$,\ $0.5$

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188. The equation of simple harmonic motion in SI is $x = 0.04\sin 10\pi t$. If the mass of the oscillating object is 200 grams, what is the equation of elastic potential energy with respect to time in SI? $(\pi^2 = 10)$
\begin{align*} &(1) u_e = 0.04\sin^2 10\pi t (2) u_e = 0.04\cos^2 10\pi t &(3) u_e = 0.16\sin^2 10\pi t (4) u_e = 0.16\cos^2 10\pi t \end{align*}

189. Referring to the displacement–time graph of two oscillators A and B, where the mass of object A is four times the mass of object B, how many times greater is the force exerted on object A compared to the force exerted on object B?
[Figure: displacement–time graph showing two sinusoidal waves; wave A has amplitude 8 cm and wave B has amplitude 2 cm, with different periods]
\begin{align*} &(1) 64 &(2) \dfrac{1}{4} &(3) 16 &(4) 4 \end{align*}

190. The velocity–time graph of a simple harmonic oscillator is shown in the figure below. Which of the time intervals shown in the figure does NOT have the greatest magnitude of average acceleration?
[Figure: velocity–time graph of simple harmonic motion showing intervals $\frac{T}{4}$, $\frac{3T}{4}$, and $T$ marked on the time axis]
$$ (1)\quad \left(\frac{T}{2} \text{ to } \frac{T}{4}\right) \text{ and } \left(\frac{3T}{4} \text{ to } \frac{T}{2}\right) $$ $$ (2)\quad \left(\frac{3T}{4} \text{ to } \frac{T}{4}\right) \text{ and } \left(0 \text{ to } T\right) $$ $$ (3)\quad \left(0 \text{ to } \frac{T}{2}\right) \text{ and } \left(\frac{T}{2} \text{ to } T\right) $$ $$ (4)\quad \left(0 \text{ to } \frac{T}{2}\right) \text{ and } \left(\frac{3T}{4} \text{ to } \frac{T}{4}\right) $$

191. A string fixed at both ends has a length of 40 cm and its fundamental frequency is 150 Hz. If the mass per unit length of the string is 20 milligrams per centimeter, what is the tension in the string in newtons?
$$ (1)\quad 14.4 \qquad (2)\quad 28.8 \qquad (3)\quad 144 \qquad (4)\quad 288 $$
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192- In the figure, a transverse wave on a string propagates at speed $20\,\dfrac{\text{m}}{\text{s}}$. If particle M completes 10 full oscillations per second, how many seconds does it take for the wave to travel distance $d$ along the x-axis?
[Figure: A transverse wave shown on x-y axes, with amplitude A, point M on the crest, point N in the trough, and distance d marked along x-axis. The wave shows amplitude $A$, $\dfrac{A}{2}$, and $-\dfrac{A}{2}$ marked on y-axis.]

• [(1)] $\dfrac{1}{10}$ (2) $\dfrac{1}{20}$ (3) $\dfrac{5}{60}$ (4) $\dfrac{7}{60}$

193- The sound intensity is $I = 3.2\times10^{-3}\,\dfrac{\text{W}}{\text{m}^2}$. The sound level in decibels is? $\left(\log 2 = 0.3,\quad I_0 = 10^{-12}\,\dfrac{\text{W}}{\text{m}^2}\right)$
(1) 15 (2) 25 (3) 85 (4) 95

194- A sound source moves at constant speed. The wavelength in front of the source is $5_0$ m and the wavelength behind the source is $6_0$ m. If the source stops, the wavelength of the emitted sound will be how many $0_0$ m?
(1) $0_0\,66$ (2) $0_0\,60$ (3) $0_0\,55$ (4) $0_0\,50$

195- If we perform Young's double-slit experiment with violet light, the width of each bright fringe is $x$, and if we perform the same experiment with yellow light, the width of each bright fringe is $x'$. If the slit separation with violet light is $1.5$ times the slit separation with yellow light, then $\dfrac{x'}{x}$ is?
(1) $\dfrac{2}{3}$ (2) $\dfrac{3}{2}$ (3) $2$ (4) $4$

196- The electric field function of an electromagnetic wave in SI is $E = E_{\max}\sin 2\pi\!\left(10^8\,t - \dfrac{x}{3}\right)$. This wave is in the ........... range.
(1) Gamma rays (2) Violet (3) Radio waves (4) Infrared

197- The longest wavelength absorbed by the hydrogen atom in the ground state is how many nanometers? $\left(R_H = \dfrac{1}{100}\,\text{nm}^{-1}\right)$
(1) 25 (2) 100 (3) $\dfrac{400}{3}$ (4) $\dfrac{100}{3}$

198- The work function of a metal is $2\,\text{eV}$. If light with frequency $2\times10^{15}\,\text{Hz}$ shines on this metal, the stopping voltage is $V_0$. If light with frequency $V_0$ shines on the metal, the stopping voltage will be how many volts? $\left(h = 4\times10^{-15}\,\text{eV.s}\right)$
(1) $1$ (2) $2$ (3) $\dfrac{1}{2}$ (4) $\dfrac{1}{3}$

199- In a solid, the distance between the last complete band and the conduction band is about 5 electron volts. This material is:
(1) Conductor. (2) Insulator. (3) Semiconductor. (4) Intrinsic semiconductor.