到底在幹嘛😵‍💫

A better resolution for the two headlights of a car in a picture can be achieved by reducing (A) the separation of the headlights; (B) the wavelength of light; (C) the aperture diameter of the camera lens; (D) All; (E) None.

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(B) the current; (C) the sign and concentration of charge carriers; (D) All; (E) None. A particle of mass m and charge q is in a circular orbit (of radius R) normal to an external field B. What is proportional to the magnetic field created at the center of its orbit by the charge? (A) m; (B) q; (C) R; (D) B; (E) None.

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for an ideal conductor; (D) All; (E) None. A conductor has a surface charge density o C/m². The force per unit area on the surface is (A) 0; (B) σ²/2 80 N/m²; (C) o²/ɛo N/m²; (D) 20² /ɛo N/m²; (E) None.

要死了🥲

Which statement is not correct for the "shear modulus"? (A) It has the same dimension as the "pressure"; (Bt involves the application of two parallel forces of opposite directions along the same line; (C) It can not be defined for an ideal fluid; (D) All; (E) None.

在講什麼😀

A rope of mass M and length L hangs vertically. What is the time I needed for a pulse to travel from the bottom end to the support? (A) 0.5 (L/g)0.5; (B) (L/g) 0.5; (C) 2 (L/g) 0.5; (D) 2 (L/g); (E) None. Which statement in want for the 66t 220

這題為何是B

Which pair of vectors is not always in parallel? (A) Velocity & linear momentum; (B) Angular velocity & angular momentum; (C) Net force & acceleration; (D) All; (E) None.

怎麼寫

If the energy needed to send an object (initially at rest on the earth's surface) to a maximum height H is a half of that for sending it into an orbit at the same height, what would be the value of H in terms of RE (the radius of the earth)? Ignore the earth's rotation. (A) 1/4; (B) 1/3; (C) 1/2; (D) 2/3; (E) None.

這題在講什麼。

A ball of mass m moves in a vertical circle at the end of a string. By how much is the tension at the bottom greater than that at the top? (A)0; (B) 2 mg; (C) 4 mg; (D) 6mg; (E) None.

這些選項在講啥😅 答案B

2. Which is not correct to apply Newton's 3rd law? (A) All measurements should be made in an inertial reference frame; (B) The interacting particles can not be accelerating; (C) No virtual force (e.g., the Coriolis force) is involved; (D) All; (E) None.

（b）怎麼算？

. 例題 (4-13) - 動能與功的合併問題 有一質量為 200 kg 的物體,其最初之動能為6,400 J , 經過 16 s 之後動能增為160,000 J,試求: I (a) 物體之初速度為若干? (b) 物體之加速度為若干 (若為等加速度)? (C) 受到的作用力有多大? (d) 在16 s 內該物體位移了多少? W = Fxd// 1 |Ex=-mv² 2