Answer:

Explanation:
h = Planck's constant = 
c = Speed of light = 
E = Energy = 
Wavelength ejected is given by

The maximum wavelength in angstroms of the radiation that will eject electrons from the metal is 
A force can be considered a push or pull
hope this helps :)
Answer:

Explanation:
We define our values according to the text,
R= Radius
Velocity
Strenght of the vortex filament
From this and in a vectorial way we express an elemental lenght of this filmaent as
. So,

Where
imply a vector acting perpendicular to both vectors.
Applying Biot-Savart law, we have,

Substituting the preoviusly equation obtained,



So we can express the velocity induced is,

Answer:
The mass is 1200 kilograms
Explanation:
Because Force is equal to mass times acceleration (F=m×a)
F=m×a
1800N=?×1.5
1800÷1.5=1200
1800N=1200Kg×1.5