Answer:
Explanation:
Let the velocity be v
Total energy at the bottom
= rotational + linear kinetic energy
= 1/2 Iω² + 1/2 mv² ( I moment of inertia of shell = mr² )
= 1/2 mr²ω² + 1/2 mv² ( v = ω r )
= 1/2 mv² +1/2 mv²
= mv²
mv² = mgh ( conservation of energy )
v² = gh
v = √gh
= √9.8 x 1.8
= 4.2 m /s
Answer:
The buoyant force is 3778.8 N in upward.
Explanation:
Given that,
Mass of balloon = 222 Kg
Volume = 328 m³
Density of air = 1.20 kg/m³
Density of helium = 0.179 kg/m³
We need to calculate the buoyant force acting
Using formula of buoyant force

Where,
= density of air
V = Volume of balloon
g = acceleration due to gravity
Put the value into the formula


This buoyant force is in upward direction.
Hence, The buoyant force is 3778.8 N in upward.
Answer:
Explanation:
27dB = 2.7 B
So I / I₀ = 10⁻²°⁷ , I₀ is intensity of main sound and I is intensity after reduction.
= 1.99 X 10⁻³
So intensity will reduce by 1.99 X 10⁻³ .
Answer:
Friction, normal force, and weight
Explanation:
If the book slows down, it means that there must be friction acting in the opposite direction of the direction the book is moving in.
Weight is caused by the gravitational pull of the Earth on the book, and normal force is the table pushing the book up because the book is pushing down on the table (3rd law.)
Note that weight and normal force is not the 3rd law action-reaction pair. The pair is the force of the book on the table and the force of the table on the book.