Answer:
(a) r = 1.062·R
= 
(b) r = 
(c) Zero
Explanation:
Here we have escape velocity v
given by
and the maximum height given by

Therefore, when the initial speed is 0.241v
we have
v =
so that;
v² =
v² = 
is then

Which gives
or
r = 1.062·R
(b) Here we have

Therefore we put
in the maximum height equation to get

From which we get
r = 1.32·R
(c) The we have the least initial mechanical energy, ME given by
ME = KE - PE
Where the KE = PE required to leave the earth we have
ME = KE - KE = 0
The least initial mechanical energy to leave the earth is zero.
Answer:
Bow Line
Explanation:
If the wind or current is pushing your boat away from the dock, bow line should be secured first.
1- We should cast off the bow and stern lines.
2-With the help of an oar or boat hook, keep the boat clear of the dock.
3-Leave the boat on its own for sometime and let the wind or current carry the boat away from the dock.
4 - As you see there is sufficient clearance, shift into forward gear and slowly leave the area.
-- The object either left or crossed the starting line exactly at time=0 .
-- The object has been traveling at constant speed for all time that
we know about.
- Demand of natural resources have influenced human settlement plans .
- Clean air,clean water and food are examples of natural resources
How demands became the obstacles ?
- The demands forces the human to go to different places in order to fulfill their requirements .
- So they have to shift their homes to different places .
Answer:
a. 2.0secs
b. 20.4m
c. 4.0secs
d. 141.2m
e. 40m/s, ∅= -30°
Explanation:
The following Data are giving
Initial speed U=40m/s
angle of elevation,∅=30°
a. the expression for the time to attain the maximum height is expressed as

where g is the acceleration due to gravity, and the value is 9.81m/s if we substitute values we arrive at

b. the expression for the maximum height is expressed as

c. The time to hit the ground is the total time of flight which is twice the time to reach the maximum height ,
Hence T=2t
T=2*2.0
T=4.0secs
d. The range of the projectile is expressed as

e. The landing speed is the same as the initial projected speed but in opposite direction
Hence the landing speed is 40m/s at angle of -30°