Question

the trust of a propeller varies jonly as the square of the number n of revolutions per secondand the fourth power of its diameter d.
a) set up the proportional relationship
b) what is the effect on T if n is doubled and d is halved?

Answer 1

Thrust/(n^2 *d^4)

T/(n^2 *d^4)
Choose values for n and d. Let n=3 and d=8
T/( 3^2 * 8^4)=
T/(9*4,096)=
T/36,864
Let T=36,864
Therefore we use this value for T and see what happens.
Now use the conditions: n is doubled and d is halved. let n = 3*2= 6 and d= 8/2 =4.
Plug in new values:
T/(6^2 * 4^4)=
T/(36 * 256)=
T/9216

36,864/9216= 4
Therefore the Thrust is increased 4 times.

Answer 2

Mertsj are you there