Answer:
Explanation:
Initially the two boys were sitting on the periphery , total moment of inertia
= 1/2 M r² + 2mr² ; M is mass of the merry go round , m is mass of each boy and r is the radius
1/2 x 200 x 2² + 2 x 40 x 2²
= 400 + 320
I₁ = 720 kg m²
Finally the two boys were sitting at the middle , total moment of inertia
= 1/2 M r² + 2m( r/2)² ; M is mass of the merry go round , m is mass of each boy and r is the radius
1/2 x 200 x 2² + 2 x 40 x 1²
= 400 + 80
I₂ = 480
Now the system will obey law of coservation of angular momentum because no torque is acting on the system.
I₁ω₁ = I₂ω₂ , I₁ and ω₁ are moment of inertia and angular velocity of first case and I₂ and ω₂ are of second case.
720 X 12 = 480 ω₂
ω₂ = 18 rad / s
<span>The burning of methane is a chemical reaction, There is a</span> change in temperature and the production of gases is the evidence. This <span>chemical change results in the formation of 1 or more new substances and a new compound is create. </span>Methane<span> burns with a smokey flame that forms carbon dioxide and water, which makes it a </span>chemical reaction.
when two sine waves are superimposed on one another, a beat pattern is observed . this beat pattern consists of high intensity and low intensity in sequence alternately. we get the high intensity pattern when the two waves meet in phase and we get low intensity when the two waves are out of phase. the intensity is lowest when the two wave are completely out of phase or 180 degree phase difference between the waves.
hence correct choice is a.180
