wally holds a pillow over his head for an hour does he do any work ? if not y? what energey changes is accouring?
To determine if Wally does any work while holding a pillow over his head for an hour, we need to understand the concept of work in physics.
In physics, work is defined as the transfer of energy that occurs when a force is applied to an object and causes it to move in the direction of that force. Work is measured in joules (J).
In Wally's situation, he is holding a pillow over his head, but he is not moving the pillow or exerting any force on it. Therefore, no work is being done because there is no displacement of the pillow in the direction of the applied force (zero distance moved).
However, even though no work is being done, there are energy changes occurring during this activity. Wally's body is using energy to support the weight of the pillow. This energy is being converted from chemical potential energy in his muscles to mechanical energy in the form of maintaining the pillow's position against gravity.
So to summarize:
- Wally does not do any work because there is no displacement of the pillow.
- Energy changes occur as Wally's body uses chemical potential energy to counteract the force of gravity and maintain the pillow's position.
It's worth mentioning that while Wally may not be doing physical work, he might still be engaging in mental or psychological work, such as concentration or focus, depending on the context of the situation.