Answer:

Explanation:
given,
width of door dimension = 1 m
mass of door = 15 Kg
mass of bullet = 10 g = 0.001 Kg
speed of bullet = 400 m/s


a) from conservation of angular momentum





Answer:
The moment of inertia is 
Explanation:
The moment of inertia is equal:

If r is 
and 


Answer:
h = 16.67m
Explanation:
If the kinetic energy of the cylinder is 510J:


Where the inertia is given by:

Replacing this value:

Speed of the block will therefore be:

By conservation of energy:
Eo = Ef
Eo = 0

So,

Solving for h we get:
h=16.67m
Answer
given,
diameter,d₁ = 7.5 cm
d₂ = 4.5 cm
P₁ = 32 kPa
P₂ = 25 kPa
Assuming, we have calculation of flow in the pipe
using continuity equation
A₁ v₁ = A₂ v₂
π r₁² v₁ = π r₂² v₂
Applying Bernoulli's equation
v₂ = 4.01 m/s
fluid flow rate
Q = A₂ V₂
Q = π (0.0225)² x 4.01
Q = 6.38 x 10⁻³ m³/s
flow in the pipe is equal to 6.38 x 10⁻³ m³/s