This thermal energy flows as heat within the box and floor, ultimately raising the temperature of both of these objects.
Answer:
0.453 m/s
Explanation:
Assuming the handle has diameter of 0.4 m while inner part diameter is 0.1 m then the circumference of outer part is
where d is diameter and subscript h denote handle. By substituting 0.4 for the handle's diameter then cirxumference of outer part is 
The rate of rotation will then be 1.81/1.256=1.441 rev/s
Similarly, circumference of inner part will be
where subscript i represent inner. Substituting 0.1 for inner diameter then

The rate of rotation found for outer handle applies for inner hence speed will be 0.3142*1.441=0.453 m/s
The force applied to the cannonball and cannon is equal. The explosion inside the cannon will generate a pressure which will turn into a force on both cannonball and cannon. The cannon being heavier and fixed to the ground will move a bit, but the cannonball will be thrown away, fired.
Thiết bị không phải nguồn điện:
Đáp án D