Conservation of Mechanical Energy

AI Thread Summary
The discussion focuses on the relationship between gravitational potential energy and elastic potential energy in the context of the Conservation of Mechanical Energy. When a spring is compressed, work done by muscles is stored as elastic potential energy in the spring. This stored energy is then transferred to a marble when the spring releases, converting it into kinetic energy. The marble's ascent against gravity illustrates the conversion of this energy into gravitational potential energy. Understanding this relationship is crucial for grasping the principles of mechanical energy conservation.
Travis Enigma
Messages
13
Reaction score
4
Homework Statement
A 5.0 g marble is fired vertically upward using a spring gun. The spring must be compressed 8.0 cm if the marble is to just reach a target 20 m above the marble’s position on the compressed spring. (a) What is the change ΔUg in the gravitational potential energy of the marble–Earth system during the 20 m ascent? (b) What is the change ΔUs in the elastic potential energy of the spring during its launch of the marble? (c) What is the spring constant of the spring?
Relevant Equations
Ug= mgh
Okay For a this is what I did.

a.
IMG_3230.jpg

I'm confused about B. I understand that it has something to do with the Conservation of Mechanical Energy, but I don't exactly know what to do.
 
Physics news on Phys.org
What exactly is the relationship between gravitational potential energy and elastic potential energy?
 
While compressing the spring of the gun, your muscles are doing certain amount of work that remains stored in the deformed spring.
That "potential" energy is eventually released and fully transferred to the marble.
The same amount of energy is used to elevate the marble certain height, while doing work against gravity.
 
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...
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}...
Back
Top