Final Project

For our final project we wanted to showcase our love for movies and film culture by diagnosing the physics behind from the movie Hobbit and the battle of the five armies. In this project we examined the physics behind each stunt and would then evaluate them as whether Orlando Bloom the character playing legolas could either pull off these stunts in the real world or if special effects would be needed.

Calculations:

1. finding the force of legolas pushing onto the stones:

this required both the mass of legolas and of the stone. Legolas was easy to find by googling up the actors weight(77kg) . The stone required more effort we had to guess which type of stone it was by googling up multiple different types of stone, we found our stone to be crushed stone. Next using the density of given stone (1600 kg/m^3) we found the dimensions of the cube like stone by using legolas's height which was a given 6 feet and then using that as a scale to find the measurements of the stone. (0.6m*0.6m*0.6m) using this we found the mass of the stone to be 345kg.

a. Using the masses and knowing the force of gravity, we also had to examine the acceleration of the two objects. We found that force of gravity was the same as earth and that legolas jumped each time to his original height therefore countering the acceleration of gravity with each jump so we estimated the acceleration of legolas in each jump was equal in magnitude to gravity. Using this we calculated the forces by adding the force of both the mass and legolas by gravity downwards. then using the force normal to be an upwards force and legolas stands on the rock and then using the force down minus the force normal of legoas to find the exact force which would counter the 345kg+77kg)(9.8m/s² ) = 4135.6N = Force downwards then the force of the push would have to be legolas's mass times 9.8m/s² to get the force of his push upwards. Fpush= 754.6N. In the force diagrams you see this initial and then force of legolas pushing up afterwards however i forgot to add the force downwards due to legolas's push which would be an equal F of 754.6 N due to every action having an equal and opposite reaction.

2. Momentum of legola's pushing on stones.

Since we knew the mass of both the stones and legolas and were able to find the horizontal velocity of legolas using distance of himself over time recorded with a stop watch this was a very easy equation to find out the momentum via p=m*v

calculations:

Momentum of legolas (x): 77(10m/s) = 770kg*m/s the

Momentum of rock(x): 345(v) = -770kg*m/s v = -.45m/s

b. with the velocity known of legolas traveling 10m/s horizontally and 10m/s vertically we were then able to find his tangential velocity up the steps to be 14.1 m/s by using the pythagorean theorem. We then plugged that inot the kintetic energy equation to find his kinetic energy was 7,546J.

3. the jump onto the orc:

didn't require much calculations as our main goal was to see if any of these scenes were possible so we recorded legolas's vertical leap to be 1.62 meters onto the orcs head which we found using legolas as a scale.

4. Legolas stabbing the orc's head

This we found by first using the breaking point of a humans skull which as measured by a variety of bicycle studies found was a breaking point of about 3425N. Next we found the maximum force Legolas could use on the orc by using his body weight time gravity which is 770N of force divided by the tiny surface area of the blade which is about 1e^-24 meters allowed a maximum force of 770/1e^-24 = 92373 Pascals which is an equivalent force to 92373 Newtons.

Analysis of data:

Now with the physics behidn each scene we are able to decide whether each scene is possible to be performed by the real life Orlando Bloom :

1. Legolas Jumping on the stones: after finding out his force of push for the first stone was 754.6N which equated to about 169 lb of force we believe this is very possible even if he did it on a single foot due to humans being able to accomplish a much stronger force of push demonstrated by the human recored squat by Andrey Malanichev when he squatted 1036 pounds in march 2019 with two legs. So dividing this by 2 Andrey could squat 518 pounds with one leg which is way more than legolas did when jumping off the stone.

2. The next physics principle we looked at was still on the stones whether a human could run at the same tangential speed of 14.1 m/s which is equal to 31 mph. This however is not possible due to the fastest human top speed set by Usain Bolts beings 27.78 mph.

3. Jumping onto the orc? This we believe to be possible since he reached a vertical height of 1.62 meters which is easily manageable for a human given the world record is 2.45 meters.

4. Lastly was breaking the orc's skull with a force of 3425 N this is very possible since the max force the actor can put with a knife is 902373N

In conclusion: the only scenes that could possibly be attempted by the actor Orlando Bloom in this action sequence is the jump onto the orc and stabbing the orc's brain. However since orcs don't live on earth the reality is that none of these scenes occurred and all of it was special effects.