Answer:
(a) Workdone = -27601.9J
(b) Average required power = 1314.4W
Explanation:
Mass of hoop,m =40kg
Radius of hoop, r=0.810m
Initial angular velocity Winitial=438rev/min
Wfinal=0
t= 21.0s
Rotation inertia of the hoop around its central axis I= mr²
I= 40 ×0.810²
I=26.24kg.m²
The change in kinetic energy =K. E final - K. E initail
Change in K. E =1/2I(Wfinal² -Winitial²)
Change in K. E = 1/2 ×26.24[0-(438×2π/60)²]
Change in K. E= -27601.9J
(a) Change in Kinetic energy = Workdone
W= 27601.9J( since work is done on hook)
(b) average required power = W/t
=27601.9/21 =1314.4W
Answer:
Distance is directly proportional to the velocity
Explanation:
In 1929, Edwin Hubble's wrote an article that talked about relationship between the distance and recession speed/velocity of galaxies which led to what is known as the Hubble Law. This law states that galaxies are moving away from the earth at velocities proportional to their distances.
Thus is written as;
v = H_o•d
Where;
v is velocity
d is distance
H_o is Hubble's constant rate of cosmic expansion.
He came to this conclusion by generating a graph known as Hubble's classic graph which was a graph of observed velocity vs distance for nearby galaxies.
Explanation:
The unit of work done is in Joules
Work done is a physical quantity that is defined as the force applied to move a body through a particular distance.
Work is only done when the force applied moves a body through a distance.
Work done = Force x distance
The maximum work is done when the force is parallel to the distance direction.
The minimum work is done when the force is at an angle of 90° to the distance direction.
So to solve this problem;
multiply the force applied by Zack and distance through which the bull was pulled.
Answer: 200 knots
Explanation: the maximum indicated airspeed at which aircraft may be flown when at or below 2,500 feet AGL and within 4 nautical miles of the primary airport of Class C airspace is 200 KNOTS
Answer:
Mass of the sled in the snow 83.33 kg.
<u>Explanation</u>:
Given that,
Force applied to move the sled in the snow (F) = 75N
We know that
Newton's second law of motion is
F = ma (Or "force" is equal to "mass" times "acceleration".)
So if we move this around we can isolate mass and get mass
M = 83.33 kg
Mass of the sled in the snow <u>83.33 kg.</u>
