Answer:
6.19 x
m/
Explanation:
For this exercise we need to sum the forces on the y-axis and x-axis as follows:
∑
= N - mg = m.
= 0
From the exercise, we deduce there is no motion in y-axis, so:
N = mg
Then for x-axis we have:
∑
= H -
= m.
= 0
Now, from the exercise we deduce that we are looking for the greatest static friction which means to have the maximun static friction to start moving, so at this point the acceleration is zero, so we can find horizontal force (H), which then will act in the airplane to move it. Therefore we have:
H =
=
=
N =
mg
H = (0.76)(84Kg)(9.8m/
)
H = 625.63 N
Now we apply this force to the weight of the plane to find the greatest acceleration the mann can give to start moving the plane.
a =
= 
a = 
a = 6.19 x
m/
Answer:
6 m/s
Explanation:
if the bus and you are moving in the same direction, then you add your speeds together
Answer: 1.39 s
Explanation:
We can solve this problem with the following equations:
(1)
(2)
Where:
is the length the steel wire streches (taking into account 1mm=0.001 m)
is the length of the steel wire before being streched
is the force due gravity (the weight) acting on the pendulum with mass 
is the transversal area of the wire
is the Young modulus for steel
is the period of the pendulum
is the acceleration due gravity
Knowing this, let's begin by finding
:
(3)
Where
is the diameter of the wire
(4)
(5)
Knowing this area we can isolate
from (1):
(6)
And substitute
in (2):
(7)
(8)
Finally:
