The three things to remember about gravitational forces in space are:
(1) The gravitational forces are inversely proportional to the square of the distance between the objects. More is the distance between the objects , less will be the gravitational force between them.
(2) The gravitational forces are the weakest of all the four fundamental forces (Nuclear forces, weak forces, electromagnetic forces, gravitational forces) in nature.
(3)Gravitational forces are always attractive . They are also conservative in nature. work done by these forces or against these forces doesn't depend on the path followed.
Answer:
(b)-3 m,-7 m
Explanation:
Displacement is a vector quantity that connects the initial position of an object to its final position after a certain motion.
Mathematically, displacement can be written as:

where
is the final position
is the initial position
The direction of this vector is from the initial position to the final position.
In order to calculate the displacement of an object, therefore, it is necessary to correctly take into account the sign of each motion, which gives the direction of each motion.
Let's analyze the three cases:
(a) -3 m, +5 m;
In this case, the object moves 3 m in the negative direction first, and then 5 meters in the positive direction; so the net displacement is
d = -3 + 5 = +2 m
(b)-3 m,-7 m;
In this case, the object moves 3 m in the negative direction first, and then 3 meters in the negative direction; so the net displacement is
d = -3 - 7 = -10 m
(c) 7 m, -3 m?
In this case, the object moves 7 m in the positive direction first, and then 3 meters in the negative direction; so the net displacement is
d = +7 + (-3) = +4 m
So, the only situation in which we have a net negative displacement is situation b).
Answer:
W=1.5×10⁸J
Explanation:
first change the km to m then you get 10000m
- W=Fd
- W=15000*10000
- W=1.5×10⁸J
When supernova explodes
because of the collapsing cores, the core itself will become a neutron star or
a white dwarf without undergoing any kind of explosive transformation. The white
dwarf stars can also become supernova if they orbit another star in a binary
system and steal material from their companion. In addition, the end state of a
star, whether it will explode as a supernova become a black hole.
A observation is gathering data.
A inference is a conclusion claimed on the basis of proof and reasoning.
Hope this helps :)