How Do You Solve the Projectile Motion Equations for Two Objects?

  • Thread starter Thread starter graten2go
  • Start date Start date
  • Tags Tags
    Projectile
AI Thread Summary
The discussion focuses on solving projectile motion equations for two objects, emphasizing the need to calculate the distance traveled by both at any instant and sum them to determine the height of a tower. Two key equations are presented: one for the first object falling from a height of 60 m and another for the second object projected upwards from ground level. The first object's equation accounts for gravitational acceleration acting downwards, while the second object's equation considers the initial velocity and the same gravitational effect. A participant suggests that there may be a mistake in the initial attempt to solve the problem, particularly regarding the position-time equation for the first object. The conversation highlights the importance of correctly applying the equations and checking for errors in calculations.
graten2go
Messages
5
Reaction score
0
Thank you for everyones help.
 
Last edited:
Physics news on Phys.org
Sorry but I didn't understand your solution. :( But my approach will be : Calculate distance traveled by them at any instant and add them up. There sum is equal to height of tower.
 
We have two variables, time and height, and two equations, one for the first object and one for the second.

The equation for the first object is x= (xi) -(vi)(t) - (1/2)(g)(t^2) , where xi= initial height= 60 m
The equation for the second object, since g is working against the motion, is x= (xi) + (Vi)(t)-(1/2)(g)(t^2), vi= initial velocity, and xi= initial position/height= 0 m


Plug in your knowns, and solve the system of equations.


------
On second look I see that you did this for your second attempt, and this is correct as far as I know-- 40.9 m. There must be a mistake in your first attempt.

Your first attempt is confusing, I can't really tell what you did. Maybe your position-time equation for the first object is incorrect. What equation did you use for your first object? Leave out units for now so I can see what you did.
 
Last edited:
I multiplied the values first without the error limit. Got 19.38. rounded it off to 2 significant figures since the given data has 2 significant figures. So = 19. For error I used the above formula. It comes out about 1.48. Now my question is. Should I write the answer as 19±1.5 (rounding 1.48 to 2 significant figures) OR should I write it as 19±1. So in short, should the error have same number of significant figures as the mean value or should it have the same number of decimal places as...
Thread 'A cylinder connected to a hanging mass'
Let's declare that for the cylinder, mass = M = 10 kg Radius = R = 4 m For the wall and the floor, Friction coeff = ##\mu## = 0.5 For the hanging mass, mass = m = 11 kg First, we divide the force according to their respective plane (x and y thing, correct me if I'm wrong) and according to which, cylinder or the hanging mass, they're working on. Force on the hanging mass $$mg - T = ma$$ Force(Cylinder) on y $$N_f + f_w - Mg = 0$$ Force(Cylinder) on x $$T + f_f - N_w = Ma$$ There's also...
Back
Top