Answer:
8.91 J
Explanation:
mass, m = 8.20 kg
radius, r = 0.22 m
Moment of inertia of the shell, I = 2/3 mr^2
= 2/3 x 8.2 x 0.22 x 0.22 = 0.265 kgm^2
n = 6 revolutions
Angular displacement, θ = 6 x 2 x π = 37.68 rad
angular acceleration, α = 0.890 rad/s^2
initial angular velocity, ωo = 0 rad/s
Let the final angular velocity is ω.
Use third equation of motion
ω² = ωo² + 2αθ
ω² = 0 + 2 x 0.890 x 37.68
ω = 8.2 rad/s
Kinetic energy,

K = 0.5 x 0.265 x 8.2 x 8.2
K = 8.91 J
The Doppler effect occurs when a source of sound or light
moves either toward or away from the observer.
The potential of electrons in a circuit can be increased by the action of a battery.
Answer:
1: 19,6 N | 2: 686 N | 3: 705,6 N
Explanation:
Just apply the formula:
1: 2 . 9,8 = 19.6 N
2: (60+10) . 9,8 = 686 N
3: [30 + (6 . 7)] . 9,8
[30 + 42] . 9,8
72 . 9,8 = 705.6 N
Just sum all the weights in the system and then multiply by gravity (9,8 in this case)
As the bright sun shines upon the water, the water slowly dissapears. This is an example of physical change because here the water is just transformed into water vapour. So only the state and the shape of the substance has changed. Its originality remains absolutely intact. In the second case where the same sunlight gives energy to the surrounding plants to convert water and carbon dioxide into sugar and oxygen gas, it is a chemical change. here new substances are formed and the identity of the original substances are lost.In chemical reactions, the mass of the product will always be the same as the mass of the reactants.