<span>Slowing an
object down is not a means of accelerating it. It actually decelerates the
motion of an object. Speeding it up, changing its direction and applying
balanced forces accelerate an object. In order for an object to accelerate, a force
must be applied. It follows Newton’s second law of motion where it states that
a body at rest remains at rest unless a force is acted upon it. When you move
an object, you are exerting a force onto it. By exerting a force on the object,
you are actually displacing it from its initial position. You cannot apply
force to the object without altering its position. Keep in mind that when you
exert work, you are exerting energy too. </span>
Answer:
- The separation will be spacelike.
- The first event can't cause the second event, as there exist an frame of reference in which both happens at the same time, in different positions, so, if there were causally connected, it will imply an instant connection, this is faster than light.
Explanation:
We can define the separation between two events (using the + - - - signature) as :

where the separation will be lightlike if is equal to zero, timelike if is positive and spacelike if is negative.
For our problem








So the separation will be spacelike, and the first event can't cause the second event, as there exist an frame of reference in which both happens at the same time, in different positions, so, if there were causally connected, it will imply an instant connection, this is faster than light.
Answer:

Explanation:
Mass and weight ain't the same thing. So, for calculating weight we would use Newton's 2nd Law of Motion i.e. Force = Mass × Acceleration.
According to question,
The mass is 20kg
Acceleration is 9.8 m/s^2
Putting the given values into the formula,
F = 20 × 9.8
F = 196N
So, the weight of the rock is 196 N
Hope it helps!<3
on a given inclined we know that net force is given by

here we know that

so here we have


so here acceleration depends directly on angle of inclination
now we also know that if height of the inclined is H and its length is L
then we can write

so the acceleration is given as

so acceleration also depends directly on height of the inclined plane