Does Work in an Inclined System Only Occur in the Y Direction?

  • Thread starter Thread starter Innuendo
  • Start date Start date
  • Tags Tags
    Work
AI Thread Summary
Work is defined as the product of displacement in the direction of the force and the magnitude of the force applied. In an inclined system, work can occur in both the x and y directions, but it is important to consider the direction of the forces involved. The force pushing the block up the incline can be decomposed into x and y components, with only the component parallel to the displacement contributing to work. The confusion arises from the relationship between the force components and gravity; while gravity does influence work, the x component can also contribute depending on the angle of the incline. Ultimately, work is a scalar quantity that depends on the effective force acting in the direction of displacement.
Innuendo
Messages
26
Reaction score
0
A block is pushed up an incline over a distance.

Now I have to find the work in the system, so my question is, does work only exist in the y direction? Is there work in the x direction of the force while pushing up the incline?
 
Physics news on Phys.org
What is work?

It is the product of the displacement along the direction of the force with the magnitude of the force applied

Vectorially work is (for constant force) F.s where [.] means dot product of the F vector and s vector

If F is not constant then W = integral of F.ds

Work is a scalar: So how can work exist in x-direction or y-direction?
 
I split the force pushing the block up the incline into two forces on the x-y coordinates, so Fx and Fy. I'm confused on whether Fx . d does any work since it is normal to the gravity. I assumed that the gravity is the only source that creates work for the F because Fy is acting parallel to the gravity, and so work is done, for the Fy component of F.
 
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}...
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...
Back
Top