Impulse and Momentum, their unit and relationship

In summary, impulse and momentum have the same unit, even though they have different physical quantities, because they are defined in terms of different physical quantities. Impulse is defined as force multiplied by time, while momentum is defined as mass multiplied by velocity. This means that while they are different quantities, they both depend on two other physical quantities. Therefore, the unit for impulse and momentum are the same, and the value of impulse can be interpreted as the change in momentum.
  • #1
Al-Physya'iy
1
0

Homework Statement



Impulse is defined as: force x time

a) Find its unit expressed in term of the base units.
b) What quantity has the same unit?
What could it mean? (Impulse = change in momentum)

Homework Equations



I = F x T
P = mv


The Attempt at a Solution



a) First, we convert the force into its base unit, and then we solve.

I = F x T
= ML/T^2 x T = ML/T

b) L/T is v so

[F x T] = [mv]
[Impulse] = [Momentum]

Therefore, momentum has the same unit as impulse.

My problem is with the second part of question b. I know without the hint given in parenthesis that impulse and momentum are related, but what is it that they want me to explain? I found the question "What could it mean?" very vague, and I don't really know how I am supposed to answer it.
 
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  • #2
Al-Physya'iy said:

Homework Statement



Impulse is defined as: force x time

a) Find its unit expressed in term of the base units.
b) What quantity has the same unit?
What could it mean? (Impulse = change in momentum)

Homework Equations



I = F x T
P = mv


The Attempt at a Solution



a) First, we convert the force into its base unit, and then we solve.

I = F x T
= ML/T^2 x T = ML/T

b) L/T is v so

[F x T] = [mv]
[Impulse] = [Momentum]

Therefore, momentum has the same unit as impulse.

My problem is with the second part of question b. I know without the hint given in parenthesis that impulse and momentum are related, but what is it that they want me to explain? I found the question "What could it mean?" very vague, and I don't really know how I am supposed to answer it.

Perhaps they are getting at the idea that the value you get for Impulse, is the value of the change in momentum.
ie impulse is not the same thing as momentum, but the "amount" of impulse certainly equals the "amount" by which the momentum changes - which is why they have the same units.
 
  • #3
Impulse and momentum have same unit means that two different physical quantities can have the same units ALTHOUGH THEY HAVE DIFFERENT NATURE.We can only differentiate between two physical quantities HAVING SAME UNIT ALTHOUGH DIFFERENT NATURE ONLY BY THE WAY IN WHICH THEY ARE DEFINED OR ON WHICH OTHER PHYSICAL QUANTITIES THEY DEPEND ON . For example:

Impulse is defined as------- Force*time or we can say it depends on two physical
quantities(by definition) ,that is, force and time whereas

Momentum is defined as ----------Mass*velocity or we can say it depends on two physical quantities(by definition),that is,mass and velocity. Thus,these two have different nature
 

Related to Impulse and Momentum, their unit and relationship

1. What is impulse?

Impulse is the change in momentum of an object over a specific period of time. It is equal to the force applied to an object multiplied by the time it is applied.

2. What is momentum?

Momentum is a measure of an object's motion, determined by its mass and velocity. It is equal to the product of an object's mass and its velocity.

3. What are the units for impulse and momentum?

The units for impulse are typically expressed as Newton-seconds (Ns) or kilogram-meters per second (kg·m/s). The units for momentum are kilogram-meters per second (kg·m/s).

4. What is the relationship between impulse and momentum?

Impulse and momentum are directly related. The impulse acting on an object is equal to the change in momentum of that object. This is known as the impulse-momentum theorem.

5. How does impulse and momentum relate to the law of conservation of momentum?

The law of conservation of momentum states that in a closed system, the total momentum remains constant. This means that the total momentum before a collision or interaction is equal to the total momentum after the collision or interaction. Impulse and momentum are both important in understanding and applying this law.

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