Explanation:
It is given that,
Mass of person, m = 70 kg
Radius of merry go round, r = 2.9 m
The moment of inertia, 
Initial angular velocity of the platform, 
Part A,
Let
is the angular velocity when the person reaches the edge. We need to find it. It can be calculated using the conservation of angular momentum as :

Here, 


Solving the above equation, we get the value as :

Part B,
The initial rotational kinetic energy is given by :



The final rotational kinetic energy is given by :



Hence, this is the required solution.
Answer:
100N
Explanation:
Newton's third law of motion
For every action, there is an equal and opposite reaction.
Therefore 100N of force is exerted by the crate on student as a reaction to his action
Answer:
0.42 m/s²
Explanation:
r = radius of the flywheel = 0.300 m
w₀ = initial angular speed = 0 rad/s
w = final angular speed = ?
θ = angular displacement = 60 deg = 1.05 rad
α = angular acceleration = 0.6 rad/s²
Using the equation
w² = w₀² + 2 α θ
w² = 0² + 2 (0.6) (1.05)
w = 1.12 rad/s
Tangential acceleration is given as
= r α = (0.300) (0.6) = 0.18 m/s²
Radial acceleration is given as
= r w² = (0.300) (1.12)² = 0.38 m/s²
Magnitude of resultant acceleration is given as


= 0.42 m/s²
Answer:
The cup with 0.5L
Explanation:
To know what amount of water you take into account the specific heat of the water. The specific heat of water is:

Thus, 4186 J of energy are needed to icrease the temperature of 1 kg water in 1°C. Then, more grams of water will need more energy.
You have that one cup has 0.5 L and the other one has 750mL = 0.75L
The second cup of water will need more heat because the amount of water contained in the second cup is greater than in the first cup with 0.5L