A rock is thrown straight up with an initial velocity of 15.0 m/s. Ignore energy lost to air friction. How high will the rock rise?
A: 1.53 m
B: 22.9 m
C: 6.50 m
D: 11.5 m
E: 13.5 m
F: 15.7 m
G: 21.5 m
H: 17.5 m
A: 1.53 m
B: 22.9 m
C: 6.50 m
D: 11.5 m
E: 13.5 m
F: 15.7 m
G: 21.5 m
H: 17.5 m
举一反三
- A rock is thrown straight up with an initial velocity of 15.0 m/s. Ignore energy lost to air friction. How high will the rock rise? A: 1.53 m B: 22.9 m C: 6.50 m D: 11.5 m
- 9.3 Air is approaching a converging-diverging nozzle with a low velocity at 20 °C and 85 kPa, and it leaves the nozzle at a supersonic velocity. The velocity of air at the throat of the nozzle is A: 82 m/s B: 98 m/s C: 313 m/s D: 343 m/s
- 在细胞动力学中，细胞周期分为以下4期 A: G，S，G，M B: G，S，G，M C: G，S，S，M D: G，S，M，M E: G，S，G，M
- 若找到_____即找到碰撞能够构成对哈希的攻击（） A: M’=M且H(M’)＝H(M) B: M’≠M且H(M’) ≠H(M) C: M’≠M但H(M’)＝H(M) D: M’=M但H(M’) ≠H(M)
- 对于报文M若找到M’使_____，即找到碰撞能够构成对哈希函数H的攻击。（ ） A: M=M且H(M’)＝H(M) B: M’≠M且H(M’) ≠H(M) C: M’≠M但H(M’)＝H(M) D: M’=M但H(M’) ≠H(M)