Momentum comparing between two bodies

[robax25]

Homework Statement

There are two objects m and 2m and Force F is applied on both objects. They move a certain distance X. Which one have greater momentum and find out 2m has √2 times more momentum than m.

Homework Equations

momentum P=mv

The Attempt at a Solution

2m has greater momentum than m because P=2m*v and second question's answer, I do not know

 

[kuruman]

2m has greater momentum than m because P=2m*v ...

Not necessarily. That would be the case if the velocities were the same. How about figuring out the acceleration of each mass and writing down some relevant kinematic equations?

 

[robax25]

impusle j=F*t,, as 2m has bigger mas than m. it takes more time to overcome certain distance x and so 2m has greater impulse than m. mv=F*t , it has greater momentum than m

 

[kuruman]

The problem with this answer is that assumes the times are the same. As I posted earlier, how about finding some accelerations and writing down some kinematic equations?

 

[robax25]

no, it ( question) says they have different time t. i do not post all conditions there.

 

[kuruman]

no, it ( question) says they have different tme t.

That's not in the statement of the problem that you posted, but I agree that the times are different. Can you give a clearer explanation than "it takes more time to overcome certain distance x" why the time for the 2m mass is longer? Also, to get the quantitative factor of $\sqrt{2}$ for the second question, you must write down kinematic equations.

 

[robax25]

That's not in the statement of the problem that you posted, but I agree that the times are different. Can you give a clearer explanation than "it takes more time to overcome certain distance x" why the time for the 2m mass is longer? Also, to get the quantitative factor of $\sqrt{2}$ for the second question, you must write down kinematic equations.

you give me some hints and I get my result.

 

[kuruman]

Hints:

How about figuring out the acceleration of each mass and writing down some relevant kinematic equations?

As I posted earlier, how about finding some accelerations and writing down some kinematic equations?

Also, to get the quantitative factor of $\sqrt{2}$ for the second question, you must write down kinematic equations.

 

[haruspex]

impusle j=F*t,, as 2m has bigger mas than m. it takes more time to overcome certain distance x and so 2m has greater impulse than m. mv=F*t , it has greater momentum than m

The problem with this answer is that assumes the times are the same. As I posted earlier, how about finding some accelerations and writing down some kinematic equations?

Robax25's argument is valid. The distances are the same, the 2m will have the lower acceleration so take longer to cover that distance, and momentum is integral of F with time it will acquire the greater momentum.
The next step is to quantify it by putting equations to that argument.

 

[kuruman]

... the 2m will have the lower acceleration ...

This is precisely what I hoped OP would understand and enunciate from the start.

 

[haruspex]

This is precisely what I hoped OP would understand and enunciate from the start.

I merely paraphrased post #3 to demonstrate the OP had already got this.