Solving Mechanics Problem: Ball, String, Fly, Velocity

  • Thread starter Thread starter grief
  • Start date Start date
  • Tags Tags
    Mechanics
AI Thread Summary
To determine the force exerted by the ball on the fly to prevent it from falling, one must consider the forces acting on the fly, which include gravitational force and the centripetal force due to the ball's circular motion. The gravitational force acting on the fly is equal to its weight, which is 2M*g, where g is the acceleration due to gravity. The centripetal acceleration required for the fly to remain on the ball is given by v^2/L, where L is the length of the string. The net force exerted by the ball on the fly must counteract the gravitational force while providing the necessary centripetal force. Understanding these dynamics allows for the calculation of the required force to keep the fly from falling.
grief
Messages
73
Reaction score
1
a ball is connected to a string with length L and is swung around a horizontal axis. On top of the ball sits a fly. At the bottom of the path, the speed of the ball is v, and I need to find what force should be exerted by the ball on the fly to keep it from falling. This is confusing to me because the only forces on the fly are downward, and I'm not sure how to combine the knowledge I have about the velocity with the forces. I also know the masses of the ball and fly(ball=M, fly=2M)
 
Last edited:
Physics news on Phys.org
I think it has to do with the fact that acceleration in a circular path is v^2/R, but I'm not sure how
 
Thread 'Variable mass system : water sprayed into a moving container'

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}...
View full post »

Similar threads

Ball on a string thrown around a spool
Replies
3
Views
878
Solving a Ball Thrown off a Cliff: How Long Does it Take?
Replies
4
Views
2K
Three conceptual questions on centripetal acceleration in a cone
Replies
5
Views
2K
Horizontal impulse on a ball at rest on a plane (with friction)
Replies
14
Views
3K
Conservation of energy problem: Ball rolling down inclined plane and then through a loop-the-loop
Replies
10
Views
2K
Calculating Theoretical Reaction Force of Ball Traveling in Semi-Circle
Replies
43
Views
4K
Find Time to Reach Top of Beaker (10 cm)
Replies
16
Views
2K
Bead on a rod which is being pulled by an ideal string with velocity v
Replies
27
Views
994
How does a mass moving up a ramp change its velocity?
Replies
5
Views
1K
Foucault Pendulum at the North Pole
Replies
9
Views
2K

Hot Threads

Recent Insights

Back
Top