Falling monkeys (Projectile motion problem)

In summary, the conversation discusses a problem involving a monkey and a coconut being thrown from a tree. The equations used to solve the problem are ΔY=VoYt+1/2gt2 and ΔY=h+y=1/2*g*t^2 for the monkey and the coconut, respectively. The conversation also discusses the monkey's velocity and the attempt to solve the problem using equations. The final solution involves finding the difference between the equations for the monkey and the coconut.
  • #1
Greywolfe1982
62
0

Homework Statement



http://img202.imageshack.us/img202/3459/phys.png

Homework Equations



[tex]\Delta[/tex]Y=VoYt+1/2gt2

The Attempt at a Solution



Rearranging the equation (using [tex]\Delta[/tex]Y=h), I get [tex]\sqrt{}2h/g[/tex] which, from what I understand, means it takes [tex]\sqrt{}2h/g[/tex] seconds for the monkey to reach the point at which the coconut was thrown. My problem is moving on from here. All I know is that the monkey is at the original height of the coconut and the coconut is some portion of b from it's starting point (for what it's worth, my guess is 9, but I'd rather not lose points that I don't have to trying to guess). Where should I go from here?

Thanks!
 
Last edited by a moderator:
Physics news on Phys.org
  • #2
If the monkey catches the ball at a distance y from the ball, for monkey
Δy = h + y = ...?...(1)
For the ball
y =...? (2)
Solve these two equations to find t.
 
  • #3
For monkey
ΔY = h + y
ΔY=1/2gt2+Vimt+1/2gt2
h is 1/2gt2, y is Vimt+1/2gt2 (Vim being the monkeys velocity after falling h meters.)

For ball
ΔY = y
ΔY = Vibt+1/2gt2

ΔY = ΔY
1/2gt2+Vimt+1/2gt2=Vibt+1/2gt2

And now I'm lost again. I tried figuring out the monkeys velocity once it reached the original height of the ball (a=Vf-Vi/t) and got
V=g[tex]\sqrt{}2h/g[/tex], put that into the monkey equation and got ΔY=g[tex]\sqrt{}2h/g[/tex]t+2(1/2gt2), simplifying to ΔY=g[tex]\sqrt{}2h/g[/tex]t+gt2. I tried to set the two equations equal to each other, getting Vibt+1/2gt2=g[tex]\sqrt{}2h/g[/tex]t+gt2. From here I'm not sure what to do - I tried to find what t was equal to, but Vib and the two degrees of t's (t and t2) are making it rather difficult. I've tried rearranging twice and got a different answer each time. Any suggestions on what I'm doing wrong, or maybe where to start for rearranging?
 
  • #4
Please help? Someone?
 
  • #5
Your equation for monkey is wrong. Initial velocity of the monkey is zero.
In time t, monkey travels
h + y = 1/2*g*t^2.--------(1)
For Ball, the initial velocity is in the upward direction.
So y = -vo*t + 1/2*g*t^2.-------(2)
Find (1) - (2).
 

FAQ: Falling monkeys (Projectile motion problem)

1. What is a "falling monkey" projectile motion problem?

A falling monkey projectile motion problem is a physics problem that involves calculating the trajectory of a projectile (in this case, a monkey) as it falls from a certain height due to the force of gravity.

2. How do you solve a falling monkey projectile motion problem?

To solve a falling monkey projectile motion problem, you need to use the kinematic equations of motion and consider the initial velocity, angle of projection, and time of flight. You also need to take into account any external forces acting on the monkey, such as air resistance.

3. What factors affect the trajectory of a falling monkey?

The trajectory of a falling monkey is affected by the initial velocity, angle of projection, and the force of gravity. External factors, such as air resistance, can also affect the trajectory.

4. Is there a formula for calculating the trajectory of a falling monkey?

Yes, there is a formula for calculating the trajectory of a falling monkey. It is the same formula used for calculating the trajectory of any projectile in a uniform gravitational field: y = y0 + xtanθ - (gx^2)/(2v0^2cos^2θ), where y0 is the initial height, x is the horizontal distance, θ is the angle of projection, g is the acceleration due to gravity, and v0 is the initial velocity.

5. How can the falling monkey projectile motion problem be applied in real life?

The falling monkey projectile motion problem can be applied to real life situations such as sports (such as baseball or football), launching rockets, and even calculating the trajectory of falling objects. It is also used in engineering to design and optimize structures and machines that involve projectiles.

Back
Top