Answers:
a) 
b) 
c) 
Explanation:
<h3>a) Mass of the continent</h3>
Density
is defined as a relation between mass
and volume
:
(1)
Where:
is the average density of the continent
is the mass of the continent
is the volume of the continent, which can be estimated is we assume it as a a slab of rock 5300 km on a side and 37 km deep:

Finding the mass:
(2)
(3)
(4) This is the mass of the continent
<h3>b) Kinetic energy of the continent</h3>
Kinetic energy
is given by the following equation:
(5)
Where:
is the mass of the continent
is the velocity of the continent
(6)
(7) This is the kinetic energy of the continent
<h3>c) Speed of the jogger</h3>
If we have a jogger with mass
and the same kinetic energy as that of the continent
, we can find its velocity by isolating
from (5):
(6)
Finally:
This is the speed of the jogger
The center of mass is given with this formula:

Velocity is:

So, for the velocity of the center of mass we have:

In our case it is:
a) Time of flight: 22.6 s
To calculate the time it takes for the cargo to reach the ground, we just consider the vertical motion of the cargo.
The vertical position at time t is given by

where
h = 2.5 km = 2500 m is the initial height
is the initial vertical velocity of the cargo
g = 9.8 m/s^2 is the acceleration of gravity
The cargo reaches the ground when

So substituting it into the equation and solving for t, we find the time of flight of the cargo:

b) 7.5 km
The range travelled by the cargo can be calculated by considering its horizontal motion only. In fact, the horizontal motion is a uniform motion, with constant velocity equal to the initial velocity of the jet:

So the horizontal distance travelled is

And if we substitute the time of flight,
t = 22.6 s
We find the range of the cargo:

Answer:
the boat would be deeped by 3200 m
Explanation:
Given that
The boat arrives back after 4 seconds
And, the speed of the sound in water is 1,600 m/s
We need to find out how much deep is the water
So,
As we know that
Distance = ( speed × time) ÷ 2
Here we divided by 2 because the boat arrives back
= (1600 × 4) ÷ 2
= 3200 m
Therefore the boat would be deeped by 3200 m