Answer:
v = 15 m / s
Explanation:
In this exercise we are given the position function
x = 5 t²
and we are asked for the average velocity in an interval between t = 0 and t= 3 s, which is defined by the displacement between the time interval
let's look for the displacements
t = 0 x₀ = 0 m
t = 3 
= 5 3 2
x_{f} = 45 m
we substitute
v = 15 m / s
I'd say a weekly news magazine.
Answer: <u>In a divergent plate boundary</u>, seafloor spreading taking place. It leads to the formation of oceans as new materials are added here along the mid-oceanic ridge. There occur volcanism and shallow-focus earthquakes.
<u>In a convergent plate boundary</u>, two plates collide to form high mountain belts and also volcanic eruptions take place. There occur long chains of volcanic as well as island arcs, in association with deep-focus earthquakes.
<u>In a transform plate boundary</u>, two plates slide past each other, conserving the plates. Shallow-focus earthquakes are generated here.
The earth has experienced various geological processes, such as weathering and erosion of rocks, earthquakes, volcanic eruptions, mass extinction events, plate tectonic movements and many more. These continuous processes have configured the present shape of the earth's surface.
For example, the breaking up of the supercontinent Pangea divided into Laurasia and Gondwanaland and subsequently formed the present scenario. This separation of continents has taken place due to the convection current that generates in the mantle.
Answer:
Momentum is given by
p
=
m
v
. Impulse is the change of momentum,
I
=
Δ
p
and is also equal to force times time:
I
=
F
t
. Rearranging,
F
=
I
t
=
Δ
p
t
=
0
−
20
,
000
5
=
−
4000
N
.
Explanation:
Momentum before the collision is
p
=
m
v
=
2000
⋅
10
=
20
,
000
k
g
m
s
−
1
.
Assuming the truck comes to a complete halt, the momentum after the collision is
0
k
g
m
s
−
1
.
The change in momentum,
Δ
p
, is initial minus final
→
0
−
20
,
000
=
−
20
,
000
This is called the impulse:
I
=
Δ
p
. Impulse is also equal (check the units) to force times time:
I
=
F
t
.
We can rearrange this expression to make
F
the subject:
F
=
I
t
=
Δ
p
t
=
−
20
,
000
5
=
−
4000
N
The negative sign just means the force acting is in the opposite direction to the initial momentum.
(This will be the average force acting during the collision: collisions are chaotic so the force is unlikely to be constant.)
