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
A: 1.53 m
B: 22.9 m
C: 6.50 m
D: 11.5 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 E: 13.5 m F: 15.7 m G: 21.5 m H: 17.5 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
- 在句子I’m your rock中， rock 的意思是 _____ 。
- 地表波在石油中传播速度为（）M/S至（）M/S；在石灰岩中传播速度为（）M/S至（）M/S.
- A 20-g bullet moving at 1 000 m/s is fired through a one-kg block of wood emerging at a speed of 100 m/s. If the block had been originally at rest and is free to move, what is its resulting speed? A: 9 m/s B: 18 m/s C: 90 m/s D: 900 m/s E: 60 m/s F: 600 m/s