Usually it is movement of the writer's hand.
The movement of the pen could have been caused by someone physically pushing or dropping it, an external force such as air currents or vibrations, or a change in the pen's environment like a sudden change in temperature.
Usually a pen is moved by a hand.
Usually a pen is moved by a hand.
The pen moves because a force is applied to it. This force could be from someone pushing or throwing the pen, gravity acting upon it, or even air currents moving it.
The pen was pushed by an external force, such as someone's hand or another object, which caused it to move. When a force is applied to an object, it can cause the object to accelerate and change its position.
what is caused by motion
Usually a pen is moved by a hand.
The pen could have been pushed or thrown by someone. It could also have been knocked off a surface due to a disturbance such as wind or shaking. Alternatively, the pen may have rolled or fallen due to gravity.
no
He must have slammed the door when leaving.
Yes.
Electrons