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.
Answer:
400ft. 32ft/s -32ft/s
Explanation:
In reality the gravitational acceleration is 9.81 so the quadratic coefficient of the function should be 9.81/2
Anyway for the sake of assumtion let us takes=160t-16t^2
ds/dt=160-32t=0
t=160/32= 5 seconds.
s=160*160/32-16*(160/32)^2= 400 mts
s=384 mts
160t-16t^2=384
i.e
16t^2-160t+384=0
t^2-10t+24=0
(t-6)(t-4)=0
t=[4,6]
we have to take t=4 because it is all the up i.e <5
velocity =v=ds/dt=160-32t
v=160-32*4=32 ft/sec still going up
for all the way down take t=6 whuch is >5
v=160-6*32=-32 ft/sec (falling down!!!)
Answer:
D. infinitely extended in all directions
Explanation:
A semi infinite solid is infinitely extended in every direction. It has a single surface and can extend when heat is applied.
The body of a semi infinite solid is idealised, that is, when there is heat present, it expands in all directions to infinity. It can be used for a thick wall because its shape can be changed when subjected to different levels of heat near its surface.
It is also expands as heat is applied because its thickness is negligible.
This idealized body is used for earth, thick wall, steel piece of any shaped quenched rapidly etc indetermining variation of temperature near its surface & other surface being too far to have any impact on the region in short period of time since heat doesn’t have sufficient time to penetrate deep into body thus thickness can be neglected
Answer: Gases have three characteristic properties: (1) they are easy to compress, (2) they expand to fill their containers, and (3) they occupy far more space than the liquids or solids from which they form. An internal combustion engine provides a good example of the ease with which gases can be compressed.
Explanation:
Answer:
True
Explanation:
This is a representation of Gauss law.
Gauss’s law does hold for moving charges, and in this respect Gauss’s law is more general than Coulomb’s law. In words, Gauss’s law states that: The net outward normal electric flux through any closed surface is proportional to the total electric charge enclosed within that closed surface. The law can be expressed mathematically using vector calculus in integral form and differential form, both are equivalent since they are related by the divergence theorem, also called Gauss’s theorem.
