Forces cause acceleration, not motion. The law of action-reaction (Newton's third law) explains the nature of the forces between the two interacting objects. According to the law, the force exerted by object 1 upon object 2 is equal in magnitude and opposite in direction to the force exerted by object 2 upon object 1.
Answer: For number 9, the children would not be able to close the box.
Explanation: The combined force of the children is 55 N. The box spring overpowers them with 60 N. I hope this helps!
Answer:

Explanation:
Given:
- mass of water,

- initial temperature of water,

- final temperature of water,

- specific heat of water,

<u>Now the amount of heat energy required:</u>



Since all of the mechanical energy is being converted into heat, therefore the same amount of mechanical energy is required.