Water flows through a pipe of
radius 0.0250 m at 1.50 m/s.
the pipe narrows to a radius of
0.0100 m. what is the new
velocity of the water?
(unit = m/s)

9.38 m/s

Explanation:

Mass is conserved.

m₁ = m₂

ρ₁ Q₁ = ρ₂ Q₂

Assuming no change in density:

Q₁ = Q₂

v₁ A₁ = v₂ A₂

v₁ π r₁² = v₂ π r₂²

v₁ r₁² = v₂ r₂²

Plugging in values:

(1.50 m/s) (0.0250 m)² = v (0.0100 m)²

v = 9.38 m/s

gpe = mass x gravity constant x height or… gpe = mgh

where… mass: measured in kilograms (kg)

gravity: gravity constant on earth = 10.00 m/s2

height: measured in meters (m)

gpe: measured in joules (j) or kilojoules (kj)

how do you solve gpe?

gravitational potential energy (gpe) is the energy an object has because of its position above the. ground.

gpe = mass x gravity constant x height or… gpe = mgh.

mass:

note: to earn full marks when solving science word problems, you must show your work:

formula.

example:

given values:

mass = 0.3 kg.