所屬科目:研究所、轉學考(插大)◆普通物理學
1. A uniform solid sphere has a moment of inertia I about an axis tangent to its surface. What is the moment of inertia of this sphere about an axis through its center?(A) I /7 (B) 2I /7 (C) 2I /5 (D) 3I /5 (E) 7I /5
2. A 4.00-kg box sits atop a 10.0-kg box on a horizontal table. The coefficient of kinetic friction between the two boxes and between the lower box and the table is 0.600, while the coefficient of static friction between these same surfaces is 0.800. A horizontal pull to the right is exerted on the lower box, as shown in the figure, and the boxes move together. What is the friction force on the UPPER box? (A) 19.3 N to the right (B) 19.3 N to the left (C) 23.5 N to the right(D) 31.4 N to the right (E) 31.4 N to the left
3. You are driving along a highway at 35.0 m/s when you hear the siren of a police car approaching you from behind and you perceive the frequency as 1310 Hz. You are relieved that he is in pursuit of a different speeder when he continues past you, but now you perceive the frequency as 1240 Hz. What is the frequency of the siren in the police car? The speed of sound in air is 343 m/s. (A) 1300 Hz (B) 1320 Hz (C) 1270 Hz (D) 1360 Hz (E) 1370 Hz
4. A 0.25 kg ideal harmonic oscillator has a total mechanical energy of 4.0 J. If the oscillation amplitude is 20.0 cm, what is the oscillation frequency? (A) 4.5 Hz (B) 1.4 Hz (C) 2.3 Hz (D) 3.2 Hz (E) 6.8 Hz
5. An 8.0-g bullet is shot into a 4.0-kg block, at rest on a frictionless horizontal surface (see the figure). The bullet remains lodged in the block. The block moves into an ideal massless spring and compresses it by 8.7 cm. The spring constant of the spring is 2400 N/m. The initial velocity of the bullet is closest to (A) 1100 m/s. (B) 1200 m/s. (C) 900 m/s. (D) 1300 m/s. (E) 1000 m/s.
6. The mean free path of a gas molecule is:(A) the shortest dimension of the containing vessel(B) the cube root of the volume of the containing vessel(C) approximately the diameter of a molecule(D) average distance between adjacent molecules(E) average distance a molecule travels between intermolecular collisions
7. A particle with a mass of 1.0 × 10-3 g and charge of +1.0 μC is released from rest at one vertical plate of a capacitor as illustrated. If the electric field between the plates is 100 V/m, how far does the particle drop before it hits the second plate? (A) 0.49 (B) 0.98 (C) 1.96 (D) 4.9 (E) 9.8 cm
8. Consider Gauss's law: \( \oint_{S} \vec{E} \cdot d\vec{A} = q/\epsilon_0 \). (A) \( \vec{E} \) must be the electric field due to the enclosed charge (B) if \( q = 0 \) then \( \vec{E} = 0 \) everywhere on the Gaussian surface (C) if the charge inside consists of an electric dipole, then the integral is zero (D) \( \vec{E} \) is everywhere parallel to \( d\vec{A} \) along the surface (E) if a charge is placed outside the surface, then it cannot affect \( \vec{E} \) along the surface
9. Electrons (mass m, charge -e) are accelerated from rest through a potential difference V and are then deflected by a perpendicular magnetic field B. The radius of the resulting electron trajectory is: (A) \( \frac{\sqrt{2eV/m}}{B} \) (B) \( \frac{B\sqrt{2eVm}}{e} \) (C) \( \frac{\sqrt{2mV/e}}{B} \) (D) \( \frac{B\sqrt{2mV}}{e} \) (E) none of these
10. A square loop of wire moves with a constant speed v from a field – free region, through a region of uniform B field as shown. Which of the five graphs correctly shows the induced current I in the loop as a function of time t?(A) (B) (C)(D)(E)
(a) 請利用光線圖畫出並說明顯微鏡的成像原理
(b) 物鏡放大率為何?目鏡角度放大率為何?整體放大率為何?
2. 一半徑為 a 的非導電圓盤,帶有均勻面電荷密度σ C/m2。在中心軸上,與盤心距離 y 處的電位為何?