Consider a grey squirrel falling out of a tree to the ground. (a) If we ignore air resistance in this case (only for the sake of this problem), determine a squirrel’s velocity just before hitting the ground, assuming it fell from a height of 3.0 m. (b) If the squirrel stops in a distance of 2.0 cm through bending its limbs, compare its deceleration with that of the airman in the previous problem.
In World War II, there were several reported cases of airmen who jumped from their flaming airplanes with no parachute to escape certain death. Some fell about 20,000 feet (6000 m), and some of them survived, with few life threatening injuries. For these lucky pilots, the tree branches and snow drifts on the ground allowed their deceleration to be relatively small. If we assume that a pilot’s speed upon impact was 123 mph (54 m/s), then what was his deceleration? Assume that the trees and snow stopped him over a distance of 3.0 m.
In the second problem, the initial velocity is given, the stopping distance is given, calculate the deceleration and compare this with the airman jumping from the airplanes and surviving due to tree branch and snow.Part (a) Step 2 of 3<p>The final velocity of the freely falling body is given by
Where is the initial velocity, is the acceleration due to gravity and is the height from where it is falling.
Now the given values are
So the final velocity is
Hence, the velocity of the squirrel, just before hitting the ground, is 59 m/s.Part (b)