Questions about the chapter on forces

Please send your discussion of these questions to sciworks@pa.uky.edu.

1. Which of these is the best example of an object that weighs approximately 1 Newton?
grape     
lemon     
cantaloupe     
watermelon     

Pulling on a tractor 2. The whole family is pulling on the tractor: they are exerting a force on it. According to the Law of Interaction (Newton's Third Law) there must be another force in the system. What is it?
A force that keeps the tractor from moving     
The weight of the tractor     
The force that the tractor exerts on the people (with the aid of the rope)     
Friction     

3. An old joke asks, "Which weighs more, a pound of lead or a pound of feathers?" Which one of these statements is correct?
The mass of the lead is greater than the mass of the feathers
The force on the lead is greater than the force on the feathers
The density of the lead is greater than the density of the feathers
The volume of the lead is greater than the volume of the feathers

4. A painter's ladder Discussion question: The painter has gone to lunch, leaving the bucket of paint hanging on the ladder.

A. Please list all of the forces that involve the ladder in any way.
Figuring out how big they are is too hard, but you should be able to say something about their direction, just from your own experiences with ladders.

B. The forces listed in part A are related to other forces by the Law of Interaction. What are these? To the extent you had anything to say about the directions of the forces in part A, make corresponding comments about these forces.