I have no intuition. Momentum problem

In summary: And remember, the force is not at the end, it is at the impact. And if the masses are travelling at different speeds, the force will be a bit more complicated. The force is NOT an instantaneous thing. It is a dynamic, a relationship. Force is a force, no matter how long it takes.]In summary, when objects with different masses collide, the force exerted by each object on the other will be equal in magnitude according to Newton's Third Law. However, the effects of the force, such as changes in velocity, may vary depending on the masses and velocities of the objects. Force is not an instantaneous thing, but a dynamic relationship between objects.
  • #1
flyingpig
2,579
1

Homework Statement



Q1) Suppose the mass of object A is greater than that of object B and that it is moving towards B, which is at rest.
Will:
A. Object A exerts a larger force on object B
B. The objects exert the same size force on each other
C. Object B exerts a larger force on object A

Q2) Suppose the mass of object A is much greater than that of object B and that object B is moving in the same direction as object A but not as fast. Predict:
A. Object A exerts a larger force on object B
B. The objects exert the same size force on each other
C. Object B exerts a larger force on object A

Q3) Suppose the mass of object A is much greater than that of object B and that both objects are at rest until an explosion occurs. Predict:
A. Object A exerts a larger force on object B
B. The objects exert the same size force on each other
C. Object B exerts a larger force on object A



The Attempt at a Solution




My so called intuition tell mse all the answer is B because of action = minus reaction. i know I am wrong...

Could anyone show me the intuiton method vs math method.
 
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  • #2
You're right, Newton's 3rd Law is the key here.
 
  • #3
flyingpig said:

Homework Statement



Q1) Suppose the mass of object A is greater than that of object B and that it is moving towards B, which is at rest.
Will:
A. Object A exerts a larger force on object B
B. The objects exert the same size force on each other
C. Object B exerts a larger force on object A

Q2) Suppose the mass of object A is much greater than that of object B and that object B is moving in the same direction as object A but not as fast. Predict:
A. Object A exerts a larger force on object B
B. The objects exert the same size force on each other
C. Object B exerts a larger force on object A

Q3) Suppose the mass of object A is much greater than that of object B and that both objects are at rest until an explosion occurs. Predict:
A. Object A exerts a larger force on object B
B. The objects exert the same size force on each other
C. Object B exerts a larger force on object A



The Attempt at a Solution




My so called intuition tell mse all the answer is B because of action = minus reaction. i know I am wrong...

Could anyone show me the intuiton method vs math method.

Your intuition is no doubt calling from the back of your mind.

Luke Skywalker heard "use the force" in Star Wars

You are hearing " Use Newtons Third law ! " in Physics.

Trust the voices you hear!
 
  • #4
PeterO said:
Your intuition is no doubt calling from the back of your mind.

Luke Skywalker heard "use the force" in Star Wars

You are hearing " Use Newtons Third law ! " in Physics.

Trust the voices you hear!

And see a medical professional.
 
  • #5
But I am using the dark forces...lead me to the right way.
 
  • #6
Okay I misread the question. It's asking the force at the impact or after? If it is after, it will always be B?

If it is at the point of contact then

1) It has to be A because B will experience a change in velocity?
2) No clue still
3) I am just going to guess that at the point of exploding, it is the same as 1)?
 
  • #7
There will be no force after impact. The impact IS where the forces are happening.

And Newton's 3rd law says the forces will be equal in magnitude. Forces ALWAYS occur in equal magnitude pairs.
 
  • #8
For a second there I confused velocity and acceleration. Anyways I htink I was right initally then.

In all cases, the force is the same because the heavier mass will probably travel a shorter distance with a slower velocity given the same force, but the light mass will travel further with a greater change in velocity. Yes?
 
  • #9
flyingpig said:
Okay I misread the question. It's asking the force at the impact or after? If it is after, it will always be B?

If it is at the point of contact then

1) It has to be A because B will experience a change in velocity?
2) No clue still
3) I am just going to guess that at the point of exploding, it is the same as 1)?

NO no no, it is always B. Newtons third law.

The size of the forces is equal. The effects of the force are different [Newtons Second law explains that one]

When the multi-kg baseball bat strikes the fraction-of-a-kg ball, the bat slows slightly, while the ball accelerates at an enormous rate [and the velocity it gains in that fraction of a second is enough to see it clear the fence before is falls back to ground]
Actually it would have to be golf - Body B was at rest

Example 3 is just the example of a rifle. Once the cartridge explodes, the rifle "recoils" slightly and the bullet heads off at extremely quickly under the influence of two forces, equal in magnitude and opposite in dirction.
 
  • #10
flyingpig said:
For a second there I confused velocity and acceleration. Anyways I htink I was right initally then.

In all cases, the force is the same because the heavier mass will probably travel a shorter distance with a slower velocity given the same force, but the light mass will travel further with a greater change in velocity. Yes?

I shall adjust your sentence - using underscore to identify deletions, and italics to show additions:

In all cases, the force is the same. because The heavier mass will have probably travel a shorter distance with a slower smaller velocity change given the same force, but the light mass will travel further withhave a greater change in velocity.

Yielding:

In all cases, the force is the same. The heavier mass will have a smaller velocity change given the same force, but the light mass will have a greater change in velocity.
 
  • #11
You're right with all Bs.

But the acceleration will be different:

ma=m'a'
a=m'a'/m

For the acceleration on the first object, be it bigger or smaller.
 

1. What is intuition and why is it important in science?

Intuition is the ability to understand or know something instinctively without the need for conscious reasoning. In science, intuition is important because it allows scientists to make connections and observations that can lead to new discoveries and advancements in their field.

2. How does a lack of intuition affect problem-solving in science?

A lack of intuition can make it more difficult to solve complex problems in science. Intuition often plays a role in guiding scientists towards potential solutions or new avenues of research. Without intuition, problem-solving may require more trial and error or rely heavily on data and logic.

3. Can intuition be developed or improved upon?

Yes, intuition can be developed and improved upon through practice and experience. By regularly engaging in critical thinking and problem-solving, scientists can strengthen their intuition and become better at making connections and recognizing patterns.

4. What can scientists do to compensate for a lack of intuition?

One way to compensate for a lack of intuition is to gather more data and approach problems with a more analytical mindset. This can help to uncover patterns and connections that may not be immediately obvious. Collaborating with other scientists who may have stronger intuition can also be beneficial.

5. Are there any benefits to having a lack of intuition in science?

While intuition is an important tool for scientists, having a lack of intuition can also have its benefits. It can lead to more thorough and methodical approaches to problem-solving, as well as a greater reliance on data and evidence. It can also prevent bias and assumptions from clouding scientific research.

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