Answer: 
Explanation:
Given
Mass of child 
speed of child is 
Moment of inertia of merry go round is 
radius 
Conserving the angular momentum

Answer:
White light viewed through a prism is an example of a visible spectrum.
Answer:
Option D. ²³⁹₉₃Np
Explanation:
Let the unknown be ʸₓA.
Thus, the equation becomes:
²³⁹₉₂U —> ⁰₋₁e + ʸₓA
Next, we shall determine the x, y and A. This can be obtained as follow:
92 = –1 + x
Collect like terms
92 + 1 = x
93 = x
x = 93
239 = 0 + y
239 = y
y = 239
ʸₓA => ²³⁹₉₃A => ²³⁹₉₃Np
Thus, the complete equation is:
²³⁹₉₂U —> ⁰₋₁e + ²³⁹₉₃Np
Answer:
(A) Angular speed 40 rad/sec
Rotation = 50 rad
(b) 37812.5 J
Explanation:
We have given moment of inertia of the wheel 
Initial angular velocity of the wheel 
Angular acceleration 
(a) We know that 
We have given t = 2 sec
So 
Now 
(b) After 3 sec 
We know that kinetic energy is given by 
Using the Equation:
v² = vi² + 2 · a · s → Eq.1
where,
v = final velocity
vi = initial velocity
a = acceleration
s = distance
<span><span>We know that vi = 0 because the ball was at rest initially.
</span><span>
Therefore,
Solving Eq.1 for acceleration,
</span></span> v² = vi² + 2 · a · s
v² = 0 + 2 · a · s
v² = 2 · a · s
Rearranging for a,
a = v ²/2·<span>s
Substituting the values,
a = 46</span>²/2×1<span>
a = 1058 m/s</span>²
<span>Now applying Newton's 2nd law of motion,
</span>
<span>F = ma
= 0.145</span>×<span>1058
F = 153.4 N</span>