What Is the Initial Velocity of a Ball Thrown Upwards from a Building?

AI Thread Summary
To determine the initial velocity of a ball thrown upwards from a 20.0m high building, the formula x = xo + vot + 1/2at^2 can be used. The total time for the ball's flight is 5.5 seconds, which is crucial for calculations. It's important to establish positive and negative directions before applying the formula to avoid confusion in the results. Properly defining these directions ensures accurate calculations of the initial velocity. Understanding these principles is essential for solving similar physics problems effectively.
petal5
Messages
26
Reaction score
0
The question is as follows:

A man stands at the edge of the roof of a building 20.0m above the ground.He throws a ball vertically straight upwards(it just misses the edge of the building as it falls back down).If the total time taken for the ball to travel from his hand to the ground is 5.5seconds what is the initial velocity of the ball?

My question is,is it correct to use the following formula to solve the problem: x=xo + vot + 1/2at^2

Thanks!
 
Physics news on Phys.org
Yes, it is. However, do be careful when dealing with the directions. Define ur +ve and -ve directions first.
 
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