Correct answer is letter B. sandstone
Answer:
Moment of inertia of the system is 289.088 kg.m^2
Explanation:
Given:
Mass of the platform which is a uniform disk = 129 kg
Radius of the disk rotating about vertical axis = 1.61 m
Mass of the person standing on platform = 65.7 kg
Distance from the center of platform = 1.07 m
Mass of the dog on the platform = 27.3 kg
Distance from center of platform = 1.31 m
We have to calculate the moment of inertia.
Formula:
MOI of disk = 
Moment of inertia of the person and the dog will be mr^2.
Where m and r are different for both the bodies.
So,
Moment of inertia 
of the system with respect to the axis yy.
⇒ 
⇒ 
⇒ 
⇒ 
The moment of inertia of the system is 289.088 kg.m^2
5 seconds is a poor time to ask about, because the speed abruptly changes at exactly 5 seconds.
Up until that time, the speed has been 1 m/s. And then, at exactly 5 seconds, it becomes zero.
_________
It's also a poor question because speed is calculated from the distance covered, but the graph shows displacement, not distance. You can't really tell the distance covered from a displacement graph.
For example, if an object happens to be moving in a circle around the place where it started, then the total distance covered keeps increasing, but its displacement is constant.
Answer:
Right now I have three.
Explanation: Thanks for the points luv ^-^.
While Jane is running has a kinetic energy, which is Ek = 1/2*m*v^2 where m is mass and v is velocity When she grabs a vine, she is going to change the kinetic energy to potential energy.
We know that potential energy is given by Ep = m*g*h where m is mass, g is gravity constant and h is height
So while running the kinetic energy is Ek = 1/2 * m * 5.2^2 = 13.52*m
Then all that energy is used to swing upward and gain potential energy
Ep = m*g*h = Ek = 13.52*m
m*9.8*h = 13.52*m
h = 13.52/9.8 = 1.38 meters
So Jane will swing 1.38 meters upward
