The rock will continue to travel in a straight line with a constant velocity for ever... The reason is, once it leaves your hand there is no force acting on the rock, so it will just continue to move in a natural motion which is constant velocity.
Explanation:
a) Density is the amount of mass in a specific amount of volume
b) Some substances are less dense than water so will float and vice versa
c) The wooden plank has less density than water due to having larger volume and vice versa with the wooden block since volume and density are inversely proportional
II) (a) They are all metals
(b) water -> Compound
oxygen -> Element
Gold-> Element
Salt-> Compound
Explanation:
Fgravity = G*(mass1*mass2)/D²
G is the gravitational constant throughout the universe.
D is the distance between both objects.
D is now reduced by a factor of 5, meaning Dnew = D/5 we get
Fgravitynew = G*(mass1*mass2)/(D/5)² =
= G*(mass1*mass2)/(D²/25) =
= 25* G*(mass1*mass2)/D² = 25* Fgravity
the new force of gravity/attraction is 25×16 = 400 units.
Answer:

Explanation:
Displacement is a vector that defines the position of a particle. The vector extends from the initial position to the final position. Therefore, the displacement only takes into account this positions, since its trajectory is not important:
