Answer:
The kinetic energy of the merry-goround after 3.62 s is 544J
Explanation:
Given :
Weight w = 745 N
Radius r = 1.45 m
Force = 56.3 N
To Find:
The kinetic energy of the merry-go round after 3.62 = ?
Solution:
Step 1: Finding the Mass of merry-go-round


m = 76.02 kg
Step 2: Finding the Moment of Inertia of solid cylinder
Moment of Inertia of solid cylinder I =
Substituting the values
Moment of Inertia of solid cylinder I
=>
=> 
=> 
Step 3: Finding the Torque applied T
Torque applied T =
Substituting the values
T = 
T = 81.635 N.m
Step 4: Finding the Angular acceleration
Angular acceleration ,
Substituting the values,


Step 4: Finding the Final angular velocity
Final angular velocity ,
Substituting the values,


Now KE (100% rotational) after 3.62s is:
KE = 
KE =
KE = 544J
<span>René Descartes suggests this.</span>
Answer:
The time interval of acceleration for the bus is 2.20 seconds
Explanation:
Acceleration is the rate of change of velocity
→ 
where a is the acceleration, v is the final velocity, u is the initial velocity
and t is the time
The given is:
The uniform acceleration = -4.1 m/s²
The bus slows from 9 m/s to 0 m/s
We need to find the time interval of acceleration for the bus
Lets use the rule above
→ a = -4.1 m/s² , v = 0 m/s , u = 9 m/s
→ 
Multiply both sides by t
→ -4.1 t = -9
Divide both sides by -4.1
∴ t = 2.20 seconds
<em>The time interval of acceleration for the bus is 2.20 seconds</em>