Simple Mechanics confusing me:S

AI Thread Summary
The discussion focuses on a physics problem involving a stone whirled in a circle before the string breaks, causing it to fly horizontally. To find the centripetal acceleration, users are advised to first calculate the time it takes for the stone to fall to the ground, which is essential for determining the initial horizontal speed. One participant initially miscalculated by assuming the final vertical velocity was zero, leading to an incorrect answer. After correcting this approach and using the time of flight, they successfully found the correct speed and centripetal acceleration. The conversation highlights the importance of accurately applying kinematic equations in projectile motion.
brandon26
Messages
107
Reaction score
0
A boy whirls a stone in a horizontal circle of radius 1.2 m and at height 1.7 m above ground level. The string breaks, and the stone flies horizontally and strikes the ground after traveling a horizontal distance of 10 m. What is the magnitude of the centripetal acceleration of the stone while in circular motion?

Please help!
 
Physics news on Phys.org
Use the kinematics of projectile motion to find the initial speed of the stone. Then use that speed to calculate the centripetal acceleration.
 
Doc Al said:
Use the kinematics of projectile motion to find the initial speed of the stone. Then use that speed to calculate the centripetal acceleration.

yes, I used V^2=u^2 + 2as , where V=0 and u is the speed to be found. But the answer comes out wrong.
 
Try finding the time it takes for the object to fall. Then use that time to calculate the horizontal speed.
 
Wicked. Got the answer right by working out the time. Thanx.
PS. i got the firwst answer wrong because I assumed that V= o , but that was false
 

Thread 'Errors and significant figures'

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...
View full post »
Thread 'A cylinder connected to a hanging mass'

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...
View full post »

Similar threads

Tension of string acting on stone moving in horizontal circular motion
Replies
19
Views
3K
Radial Acceleration on a string
Replies
4
Views
2K
What is the Centripetal Acceleration of a Stone in Circular Motion?
Replies
7
Views
5K
'They' haven't considered centripetal acceleration
Replies
24
Views
2K
Stone being tossed from mountain Uni Physics with Calc
Replies
14
Views
2K
Circular motion, string and ball in a horizontal circle
Replies
9
Views
4K
Calculating Tidal Range (Gravitation)
Replies
12
Views
2K
Mechanics -projectile motion calculating angle
Replies
15
Views
4K
Box attached to end of a string, what is the max velocity?
Replies
1
Views
1K
Calculating Spring Compression for Stone Sliding Down Hill
Replies
2
Views
7K

Hot Threads

Recent Insights

Back
Top