Bruce Willis vs. helicopter bad guy

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In summary, the conversation discusses a problem involving Bruce Willis driving his car up a ramp to crash into a helicopter. The variables and equations for the problem are given, and the goal is to find the speed of the car when it leaves the ramp and the time it is flying through the air. After some calculations, it is determined that the car's speed is 19m/s, and the time in the air can be found using this value.
  • #1
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Homework Statement


Bruce Willis is driving his car up a 30° ramp in an attempt to crash into a helicopter. The ramp is 2 meters high, the helicopter is 10 meters away from the edge of the ramp and 6 meters from the ground.

Find the speed of his car when it leaves the ramp and time he is flying through the air.


Homework Equations



[tex]x = x_0 + v_0 cos(30°) t[/tex]
[tex]y = y_0 + v_0 sin(30°) t - \frac{1}{2} gt^2[/tex]


The Attempt at a Solution



To put it simply, I have two variables and two equations. Simple enough.

[tex]t = \frac{10m}{v_0 cos(30°)}[/tex]

Putting t into the latter equation I get.

[tex]8m = 2m + v_0 sin(30°)\ \frac{10m}{v_0 cos(30°)}\ -\ \frac{1}{2}\ 9.8\frac{m}{s^2}\ (\frac{10m}{v_0 cos(30°)}^2)[/tex]

[tex]v_0 = \sqrt{\frac{428.3 m^2}{3 s^2}} = 11.95m/s = 43 km/hour[/tex]

This is where I freeze up. I'm 98% sure that what I'm doing is right. Yet 43 km/hour for a car to get a helicopter 4 meters above you and 10 meters away, that sounds dodgy.

Also, If I increase the height of the helicopter above the ground I get a negative under root. But that's probably because the helicopter is so far above that no matter how fast you're going, you would just go under it in a straight line.

Is this correct?
Thanks for your help.
 
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  • #2
I think i know why you're getting some issues. Is it possible that the question is asking what the time flying through the air is and instead, you're finding the time is takes to get to the helicopter??
 
  • #3
ive done it and the answer i get is approx 19m/s, which looks to me like it could be right.

looking at your answer, i don't see where you get the 8m in there. But if you solve for v in the x equation, then sub that into the y equation to find t, then sub that t back into the x equation, i don't really see where you could go wrong.
 
  • #4
and you are right about the negative root. unless you put some wings on the car and calculate some thrust:)
 
  • #5
dacruick said:
I think i know why you're getting some issues. Is it possible that the question is asking what the time flying through the air is and instead, you're finding the time is takes to get to the helicopter??

The time to get to the helicopter is the one I need. Sorry about that. And those 8m are supposed to be 10m. My bad again.

19m/s is a lot better. I went the other way and solved the time from the x-equation and put it in the y-equation to solve V_0. Don't know what went wrong.

Cheers. :)
 
  • #6
either way you can find the time with that 19 metres. with that 19m you have initial velocity and an initial angle, you can definitely find the time in the air from that.
 

1. Who is Bruce Willis?

Bruce Willis is an American actor, producer, and singer best known for his roles in action films such as Die Hard, Armageddon, and The Sixth Sense.

2. Who is the helicopter bad guy?

The helicopter bad guy refers to the antagonist in the film Die Hard, a German terrorist named Hans Gruber who hijacks a building and holds its occupants hostage.

3. What is the plot of "Bruce Willis vs. helicopter bad guy"?

The plot of "Bruce Willis vs. helicopter bad guy" is centered around the character of John McClane (played by Bruce Willis), a New York City police officer who must single-handedly take on a group of terrorists led by Hans Gruber, who have taken over his wife's workplace in Los Angeles.

4. What is the significance of the helicopter in the film?

The helicopter serves as a symbol of the terrorists' power and control over the situation. It is also used as a tool for their escape and to cause destruction, adding to the tension and danger in the film.

5. Is "Bruce Willis vs. helicopter bad guy" based on a true story?

No, "Bruce Willis vs. helicopter bad guy" is not based on a true story. It is a work of fiction and was inspired by the novel "Nothing Lasts Forever" by Roderick Thorp.

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