Yahoo奇摩 網頁搜尋

  1. you have to know two equation Work=Force*Displacement Force=Mass*Acceleration 10N let 10kg to 1m/s^2 (Acceleration) 10s ->speed to 20m/s it moves (20m/s+10m/s)*10s/2=150m ( Displacement= Area on a...

  2. 1. a) F = (mv-mu)/t = (0.5×1 - 0.5×2)/0.05 = -10N ∴ The force acting on the stone is 10N backward. b) By Newton's 3rd law, force acting on the stone = -force acting on the can ∴ The force acting on the can during the collision...

  3. ...horizontal. 2014-12-24 16:29:46 補充: The physical reason behind is straight forward . The magnetc force acted on the coil, when its plane is horizontal...

  4. ... 1 and 2 are correct. The reason is straight forward . 2014-10-21 15:46:23 補充: 6.(cont'd)... Statement 3 is correct...

  5. ...gt;= Va). Then B will be observed as moving forward from A with a speed higher than that of A. Therefore...

  6. It is zero. W = F·S Now. direction of F is downward and S forward . It gives W=|F||S|cos(90⁰) = 0

  7. ..., change of momentum of gas = 250 x 2000 kg.m/s = 500,000 Kg.m/s Forward thrust = rate of change of momentum = 500 000 N (b) Acceleration of the...

  8. ...collide and drop in speed, the boys inside the car are still moving forward because of inertia. The gives their bodies a feel of...

  9. ... you are in a moving bus, you are travelling forward at the same speed with the bus. If you jump up, your speed with the bus...

  10. ... equal, and the collision is perfectly elastic. Car B would travel forward with the same speed as that of car A before collision. (2) Car A...