Answer:
Physical quantity is a physical property of an object or material that can be expressed by magnitude and unit.
The derived physical quantities are the type of physical quantities which can be expressed or defined by other physical quantities, called the base quantities. Example: Area, Volume, Velocity
Area- SI Unit: m², U.S. Customary unit: acre
Volume- SI Unit: m³, U.S. Customary unit: cubic inch
Velocity- SI Unit: m/s, U.S. Customary unit: ft/s
Answer:
The velocity of the truck after the collision is 20.93 m/s
Explanation:
It is given that,
Mass of car, m₁ = 1200 kg
Initial velocity of the car, 
Mass of truck, m₂ = 9000 kg
Initial velocity of the truck, 
After the collision, velocity of the car, 
Let 
is the velocity of the truck immediately after the collision. The momentum of the system remains conversed.
So, the velocity of the truck after the collision is 20.93 m/s. Hence, this is the required solution.
Answer:
588 J
Explanation:
PE (potential energy) = (mass) x (gravity) x (height)
mass = 12 kg
gravity = 9.8m/s^2
height = 5 m
PE = (12) x (9.8) x (5) = 588 J (Joules)
Earth's land and ocean surface to the atmosphere.
Answer:
Explanation:
Let the initial rotational inertia be I and final rotational inertia be I / 6 .
Let the initial angular velocity be ω₁ and final angular velocity be ω₂.
Applying conservation of angular momentum law
I x ω₁ = I / 6 x ω₂
6 ω₁ = ω₂
initial rotational kinetic energy = 1/2 I x ω₁ ²
Final rotational kinetic energy = 1/2 ( I / 6 ) x ω₂ ²
Final rotational kinetic energy / initial rotational kinetic energy
= ( 1 / 6 ) x ω₂ ² / ω₁ ²
= ω₂ ² / 6ω₁ ²
= 36 ω₁ ² / 6ω₁ ²
= 6 .
