Archived Problem 6 Vrms Formula: Mass in kg?

Thread starter microsd
Start date Nov 29, 2014
Tags

Formula Mass

AI Thread Summary

The discussion centers on the Vrms formula, specifically questioning whether mass must be expressed in kilograms due to the use of Joules (J) in the formula. Vrms refers to root-mean-square speed, which is a statistical measure of the speed of particles in a system. Joules, the unit of energy, is defined in terms of kilograms, indicating that mass should indeed be in kilograms for consistency. Participants highlight the importance of having access to the same textbook for clarity. Understanding these concepts is crucial for solving related physics problems effectively.

Nov 29, 2014

microsd

On problem #6, when using the Vrms formula, does the mass have to be in kg because the constant used uses J, which is kg?

Physics news on Phys.org

Nov 29, 2014

Dr.D

What on Earth is the Vrms formula, and what is J?

Are you aware that the rest of us do not have your textbook, or if we do, it is not opened to the same page you are on?

Nov 29, 2014

microsd

Vrms is root-mean-square speed and J is Joule.

Thread 'I've come across another fluid pressure problem I don't understand'

Neglect gravity other than that of water; neglect friction. F1=ρgsh=1000*10*1*(1+4)=50000 N; F1=ρgsh=1000*10*0.1*4=4000 N; F3=50000-4000=46000 N?

View full post »

Thread 'Struggling to understand the concept of this question (ice cube in water optics question)'

TL;DR Summary: I came across this question from a Sri Lankan A-level textbook. Question - An ice cube with a length of 10 cm is immersed in water at 0 °C. An observer observes the ice cube from the water, and it seems to be 7.75 cm long. If the refractive index of water is 4/3, find the height of the ice cube immersed in the water. I could not understand how the apparent height of the ice cube in the water depends on the height of the ice cube immersed in the water. Does anyone have an...

View full post »

Thread 'Variable mass system : water sprayed into a moving container'

Starting with the mass considerations #m(t)# is mass of water #M_{c}# mass of container and #M(t)# mass of total system $$M(t) = M_{C} + m(t)$$ $$\Rightarrow \frac{dM(t)}{dt} = \frac{dm(t)}{dt}$$ $$P_i = Mv + u \, dm$$ $$P_f = (M + dm)(v + dv)$$ $$\Delta P = M \, dv + (v - u) \, dm$$ $$F = \frac{dP}{dt} = M \frac{dv}{dt} + (v - u) \frac{dm}{dt}$$ $$F = u \frac{dm}{dt} = \rho A u^2$$ from conservation of momentum , the cannon recoils with the same force which it applies. $$\quad \frac{dm}{dt}...

View full post »