A2 level physics notes part 1

GRAVITATIONAL FIELDS
↳ a
region in space where a mass
experiences a gravitational force

↑ rector



V
- ↓ arrows show : direction of gravitational force
&
-

spacing of field shows :
Strength of gravitational field
> EARTH [ (further apart =
weaker) e .



. Jupiter /larger)
g will be closer


T T
↑ radial : field lines diverge radially from earth centre

M




↳ all objects are attracted towards centre of earth


I-
Xi
·
centre of mass which
*


-
7
-r
point at we consider total mass of object to be concentrated
↓ earth benaves as a
point mass




on earth :




Earth's gravitational field is uniform

the
weight stays same
:
~ ~ v Vv




Newton's law of universal gravitation :
2 point masses attract
each other force
w that's directly proportional to product of their masses and

inversely proportional to the square of their separation


M
⑳ F
M FcMm F2
·
Fa &
distance
?

Si &
r
·
to make into equation :
constant
particles/point masses
↓
GM Mz
F universal
,

· =


w2
gravitational
constant
2

7 x10 -"NM2kg
=




= 6 .

,
,
,