AS
work done =W = F.d = F d cosФ (Ф is angle between force F and displacement d) If a body/object is moving on a smooth surface (friction-less surface ) .There is no force acting on that body. F=0 so W=FdcosФ= (0)dcosФ ⇒ W=0
Now if a body is facing some amount of force but under the action of force there is no displacement covered. d=0 so W =FdcosФ= F(0)cosФ ⇒W=0
example: A person is applying a force on rigid wall but wall remains at rest there is no displacement occurs in wall.
The third term upon which work done dependent is angle between force and displacement i.e Ф. If Ф=90° then W= FdcosФ= Fdcos90⇒ W=0 ( as cos 90°=0)
The energy carried by a single photon of frequency f is given by:
where
is the Planck constant. In our problem, the frequency of the photon is
, and by using these numbers we can find the energy of the photon:
Answer:
Explanation:
gravitational acceleration of meteoroid
= GM / R²
M is mass of planet , R is radius of orbit of meteoroid from the Centre of the planet .
R = (.9 x 6370 + 600 )x 10³ m
= 6333 x 10³ m
M , mass of the planet = 5.97 x 10²⁴ kg .
gravitational acceleration of meteoroid
= GM / R²
= (6.67 x 10⁻¹¹ x 5.97 x 10²⁴ kg / (6333 x 10³ m)²
9.92m/s²
The pressure at 100 meters below the surface of sea water with a density of 1150kg is 145.96 psi.
