Welcome to OnlineConversion.com Forums 

Convert and Calculate Post any conversion related questions and discussions here. If you're having trouble converting something, this is where you should post. * Guest Posting is allowed. 

Thread Tools  Display Modes 
#1




Kg m/s N s and N
What is the difference between Kg m/s and Newtons when talking about the average force? This is for a problem regarding momentum and impulse, etc.

#2




Re: Kg m/s N s and N
Newtons are a measure of force. An average force would also be measured in newtons. In contrast, momentum and impulse are measured in kg·m/s.
When a force is applied to an object for a period of time, the force delivers an impulse to the object. An impulse is a change in momentum: Force x Time = Impulse = Change in momentumNow, if you divide the impulse by the time during which the force was applied, you obtain the average force during that time: Avg force = Impulse ÷ TimeRemember, the units of momentum and impulse are kg·m/s. So, dividing an impulse by time gives you kg·m/s^{2}. But kg·m/s^{2} is exactly how a newton is defined: 1 newton = 1 kg·m/s^{2}And newtons are a measure of force. So, when you divide the impulse by time, you are calculating the (average) force. 
#3




Re: Kg m/s N s and N
Im just wondering I have data in N/s is this the same as kg.m/s or how do i change it to kg.m/s
Thanks in advance 
#4




Re: Kg m/s N s and N
looks to me like you still need to find a distance something moved over that time to get power.

#5




Re: Kg m/s N s and N
"Im just wondering I have data in N/s is this the same as kg.m/s or how do i change it to kg.m/s
Thanks in advance " Answer: Doing problems like this requires unit analysis. Newton=mass(kg)*acceleration due to gravity(m/s^2)=kg*m/sec^2 Time=sec The only way to relate time and force the way you request is to multiply the two N*Time=(kg*m/sec^2)*sec=kg*m/sec or N*s *the sec^2 in the denominator is canceled out to a single sec by the unit of time in the numerator of the multiplier the unit analysis for N/s is as follows: N=(kg*m/sec^2)*(1/sec)=kg*m/s^3 Depending on the context of the problem you may or may not be able to use these units. For example, if you know that a force of 20 N was applied to hold a box in static equilibrium for one minute, then it is known that 1200 N*s or 1200 kg*m/sec is applied to the box. this is the only type of problem I can think of relating the two. hope this helps 
#6




Re: Kg m/s N s and N
It seems unlikely that you would have a measurement in N/s. That would be (as stated above) a unit of kg.m/s3, which seems strange.
Is it possible that your unit is actually N.s? (That is, Newtons * seconds). That would in fact be equal to kg.m/s, which is what you wanted. 
#7




Re: Kg m/s N s and N
Quote:
However, the derivative of force with respect to time is also important, dF/dt = m*da/dt. The derivative of acceleration, da/dt, is known as jerk, and is closely related to "ride quality" in everything from cars to elevators (Amusement park rides may consider high jerk good). As both have uses, I think we need a better description of the data and its meaning or use from the poster who asked the question. 
#8




Re: Kg m/s N s and N
It is possible to have N/s units.
Consider calculating the power required for a motor moving fluid. The fluid has a weight of so many N, is moving up a distance of so many m, and this is happening each s. So, the power required would be in (N/s)*m = W. But what is the name of this intermediate unit in kg m / s3? It seems to have no name. 
#9




Re: Kg m/s N s and N
THANK YOU SO Much
Quote:

#10




Re: Kg m/s N s and N
helo guys am realy gr8ful you guys have just saved me

Thread Tools  
Display Modes  

