2.Reducing the friction between the wagon wheels
3.Reducing the length of the wagon handle
4.Increasing the friction between the wagon wheels
Answer:
2.Reducing the friction between the wagon wheels
Explanation:
If the friction between the wagon wheels and the rail is reduced, then less force will be needed to pull the wagon up. This is because the friction force goes in the opposite direction of the movement, that is, friction force opposes the desired movement, making it more difficult.
Answer:
the pressure difference will be ΔP= P₂ - P₁ =29348.64 Pa
Explanation:
from Bernoulli's equation
P₁ + ρgh₁+ 1/2ρv₁²= P₂ + ρgh₂+1/2ρv₂²
where P = pressure , ρ= density , g= gravity , h= height , v=flow speed and 1 and 2 denote first and second segment respectively
then since the pipe is horizontal there is no difference in height (h=h₁=h₂) , thus
P₁ + 1/2ρv₁²= P₂ + 1/2ρv₂²
the pressure difference ΔP= P₂ - P₁ will be
ΔP= P₂ - P₁ = 1/2ρv₁² - 1/2ρv₂² = 1/2*ρ* (v₁² - v₂²)
replacing values
ΔP= 1/2*ρ* (v₁² - v₂²) = 1/2 *1145 kg/m³ * [(7.33 m/s)² - (1.57 m/s)²] = 29348.64 Pa
ΔP= 29348.64 Pa
Answer:
Gravitational potential energy
Explanation:
The gravitational potential energy is the energy that an object has because of its positive with respect to a certain reference level (generally assumed to be the ground level).
The magnitude of the gravitational potential energy is given by
where
m is the mass of the object
g is the strenght of the gravitational field
h is the height of the object with respect to the reference level
From the formula, we see that the higher the object is, the larger its gravitational potential energy is.
Answer:
w=mg
w=[75][9.8]
w=735
Explanation: