Answer:
Part a)
acceleration = -0.042 m/s/s
Part b)
initial speed = 14.17 m/s
final speed = 5.77 m/s
Explanation:
Part a)
Let the initial velocity of the motorcycle is

now at the end of 80 s let the speed is

after another 120 s let the speed will be

now we know that



also we know that

also we have


now we can say

also we know



Part b)
now we have



so the starting velocity of the trip is

now speed after t = 200 s is given as



Answer:
2km
Explanation:
Given data
We are told that the direction traveled are
North>>>East>>>South
Hence the displacement is defined as the distance away from the initial position is
Initial position =18km
FInal position = 16km
The displacement = 18-16= 2km
Hence the displacement is 2km
Answer:
The height of the object is 5007.4 miles.
Explanation:
Given that,
Weight of object = 200 lb
We need to calculate the value of 
Using formula of gravitational force

Put the value into the formula



We need to calculate the height of the object
Using formula of gravitational force

Put the value into the formula





Hence. The height of the object is 5007.4 miles.
Answer:

Explanation:
Given:
angular speed of rotation of friction-less platform, 
moment of inertia with extended weight, 
moment of inertia with contracted weight, 
<u>Now we use the law of conservation of angular momentum:</u>



The angular speed becomes faster as the mass is contracted radially near to the axis of rotation.