00:01
A 20 -ton airplane lands on an aircraft carrier with a speed of 50 meters per second.
00:08
And as it lands, it approaches an arresting wire, which acts like a spring and also base hook slow.
00:18
This arresting wire will cause the plane to stop.
00:23
It will help the plane in stopping as the wire gets stretched.
00:29
So the measure of the wire stiffness, which is just the force constant, if it's a spring or the spring constant, is given as 3 .3 times 10 to the 8th neutons per meter.
00:42
We are to determine the following, a, what is the kinetic energy of the plane as it lands on the deck? and b, what is the amount of wire stretching as the plane halts or stops? so the first part of the problem is just a very straightforward question wherein we will just determine the kinetic energy in the initial state.
01:06
So the landing on the deck is the initial state.
01:10
The stretching of the wire and the stopping of the plane will be the final state, as shown by 0 .2 here.
01:17
So kinetic energy in the initial state is the unknown.
01:21
We have everything that we need.
01:23
We have the mass of the plane and the initial speed of the plane.
01:29
Now, 20 tons, this is not yet in mks unit, but we know that one metric ton is equivalent to 1 ,000 kilograms.
01:40
So, in other words, the mass is just 20 ,000 kilograms, since this is an airplane, of course.
01:49
It's very massive.
01:50
So do not forget to convert it.
01:52
Otherwise your answer will be very off.
01:57
Then we have 50 meters per second squared.
02:00
So plugging in these numbers into your calculator and rounding off your answer to two significant figures.
02:07
The kinetic energy of the plane as it lands on the aircraft carrier is 2 .5 times 10 to the 7th joules...