Answer:
115 m/s, 414 km/hr
Explanation:
There are two forces acting on a skydiver: gravity and air resistance (drag). At terminal velocity, the two forces are equal and opposite.
∑F = ma
D − mg = 0
D = mg
Drag force is defined as:
D = ½ ρ v² C A
where ρ is the fluid density,
v is the velocity,
C is the drag coefficient,
and A is the cross sectional surface area.
Substituting and solving for v:
½ ρ v² C A = mg
v² = 2mg / (ρCA)
v = √(2mg / (ρCA))
We're given values for m and A, and we know the value of g. We need to look up ρ and C.
Density of air depends on pressure and temperature (which vary with elevation), but we can estimate ρ ≈ 1.21 kg/m³.
For a skydiver falling headfirst, C ≈ 0.7.
Substituting all values:
v = √(2 × 80.0 kg × 9.8 m/s² / (1.21 kg/m³ × 0.7 × 0.140 m²))
v = 115 m/s
v = 115 m/s × (1 km / 1000 m) × (3600 s / hr)
v = 414 km/hr
The one with the higher frequency has more energy than the other.
Answer:
Weight = 966 Newton.
Explanation:
Given the following data;
Length = 1.2 m
Width = 2.3 m
Pressure = 350 Pa
To find the weight of the tank;
We know that weight is the force of gravity acting on an object multiplied by its mass.
Weight = mg = force
Hence, we would determine the force using the parameters that were given.
But we would first determine the area of the rectangular tank.
Area of rectangle, A = length * width
A = 1.2 * 2.3
A = 2.76 m²
Mathematically, pressure is given by the formula;
Pressure = force/area
Force = pressure * area
Substituting into the formula, we have;
Force = 2.76 * 350
Force = 966 Newton
Therefore, the weight of the tank is 966 Newton.
Answer:
The answer to your question is D An annual weather pattern
Explanation:
Reduce friction because friction just makes things harder
