Explanation:
Let h is the height of the plane above ground. x is the horizontal distance between the ground and the airport. Let s(t) is the distance between the plane and the airport. So,
...........(1)
Given, h = 4, x = 40 and s(t) = -20 mph
Differentiate equation (1) wrt t


When x = 40, 



So, the speed of the airplane is 241.14 m/s. Hence, this is the required solution.
Chemical energy stored in the compounds caked on the head of the match, and later the
chemical energy stored in the wood, was released in the form of heat and light when the
chemical compounds got hot enough.
Given :
Object A is 71 degrees and object B is 75 degrees .
To Find :
How will thermal energy flow.
Solution :
We know, by law of thermodynamics thermal energy will flow from higher temperature to lower temperature.
So, in the given question energy will flow from object B from object A.
Hence, this is the required solution.
The resultant vector is 11√2 km due north east.
<h3><u>Explanation:</u></h3>
The vector is a type of quantity which has both magnitude and direction. This quantities when expressed needs to specify both magnitude and direction.
We need to calculate the magnitude and direction separately.
Here firstly for the magnitude,
The magnitudes are both 11 km and they are at right angles to each other.
So, the resultant magnitude = √(11² +11²) km
=11√2 km
Now for the direction, one vector is due north and the other is due east.
So the resultant vector is due north east.
So the final vector is 11√2 km due North-East.