Starting from rest several toy cars roll down ramps at different

  • Thread starter Thread starter grasjm36
  • Start date Start date
  • Tags Tags
    Cars Rest Roll
AI Thread Summary
The discussion centers on the speed of toy cars rolling down ramps of varying lengths and angles. It is established that the velocity at the bottom of an incline is independent of both the angle of inclination and the length of the ramp, based on the principle of conservation of energy. Participants clarify that this independence applies to the speed just before leaving the ramp, although the speed on horizontal ground decreases afterward. The conversation emphasizes understanding the physics behind motion and energy conservation. Overall, the key takeaway is that the final speed of the cars is not affected by the ramp's characteristics.
grasjm36
Messages
2
Reaction score
0
Starting from rest several toy cars roll down ramps at different lengths and angles. Rank them according to their speed at the bottom of the ramp from slowest to fastest. Car A goes down a 10m ramp inclined at 15 degrees, Car B goes down a 10 m ramp inclined at 20 degrees, car C goes down a 8 m ramp inclined at 20 degrees and Car D coes down a 12 m ramp inclines at 12.
 
Physics news on Phys.org
Welcome to PF.
Velocity at the bottom of an incline is independent of angle of inclination and length of inclines.
 
thank you
 
Always Game.
 
physixguru said:
Welcome to PF.
Velocity at the bottom of an incline is independent of angle of inclination and length of inclines.

? Can you explain?
 
physixguru said:
Velocity at the bottom of an incline is independent of angle of inclination and length of inclines.

(physixguru means length as opposed to height.)

Hint: this follows from conservation of energy - can you see why?

Also, don't forget that that's only half the problem: the speed immediately after leaving the ramp (on the horizontal ground) is a lot less than the speed immediately before leaving the ramp (that's pretty obvious if the ramp is almost vertical, but it's still true for small angles). :smile:
 
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