Answer:
t_total = 23.757 s
Explanation:
This is a kinematics exercise.
Let's start by calculating the distance and has to reach the limit speed of
v = 18.8 m / s
v = v₀ + a t₁
the elevator starts with zero speed
v = a t₁
t₁ = v / a
t₁ = 18.8 / 2.40
t₁ = 7.833 s
in this time he runs
y₁ = v₀ t₁ + ½ a t₁²
y₁ = ½ a t₁²
y₁ = ½ 2.40 7.833²
y₁ = 73.627 m
This is the time and distance traveled until reaching the maximum speed, which will be constant throughout the rest of the trip.
x_total = x₁ + x₂
x₂ = x_total - x₁
x₂ = 373 - 73,627
x₂ = 299.373 m
this distance travels at constant speed,
v = x₂ / t₂
t₂ = x₂ / v
t₂ = 299.373 / 18.8
t₂ = 15.92 s
therefore the total travel time is
t_total = t₁ + t₂
t_total = 7.833 + 15.92
t_total = 23.757 s
The answer is option D a gallon of gasoline.
Explanation:
A gallon of gasoline has the least chemical energy. The energy content of gallon of gasoline is about 132,000 Btu. The gasoline produced is equivalent in energy terms to 4 kilowatt hours.
Gasoline has chemical potential energy stored in chemical bonds. Gasoline is called as gas or petrol, mixture of volatile, flammable liquid hydrocarbons are used as fuel for internal- combustion engines. It is used as solvent for oils and fats.
Gasoline gallon equivalent is the alternative fuel taken to equal the energy content of one liquid gallon of gasoline.
Answer:
The sum of the lengths of the sides is 2292 yards and the sum of the lengths of the triangle is 3056 yards
Explanation:
Since y represents the length of fence that is opposite (parallel) to the river and x represent the length of fence perpendicular to the river.
Therefore since we can use 3,056 yards of fencing
Side perpendicular to the river = x and,
Side opposite to the river = y = 3056 - 2x
The area of the rectangle formed (A) = Perpendicular side × Parallel side
∴ A = x(3056 - 2x) = 3056x - 2x²
A = 3056x - 2x²
To maximize the area, A' (dA/dx) = 0
∴ A' = 3056 - 4x = 0
3056 - 4x = 0
4x = 3056
x = 764 yards
y = 3056 - 2x = 3056 - 2(764) = 1528 yards.
Side perpendicular to the river = 764 yards and,
Side opposite to the river = 1528 yards
The sum of the lengths of the sides = 764 + 1528 = 2292 yard and the sum of the lengths of the triangle = 764 + 764 + 1528 = 3056 yards
Answer:
Da=(1/4)Db
Explanation:
t = Time taken
u = Initial velocity
v = Final velocity
s = Displacement
a = Acceleration due to gravity = 9.81 m/s²
When s = Da, t = t
When s = Db, t = 2t
Dividing the two equations
Hence, Da=(1/4)Db
Answer:
2.72×10^-7
Explanation:
velocity = frequency × wavelength
2.05×10^8=7.55×10^14 wavelength
wavelength = 2.05×10^8/7.55×10^14
wavelength = 2.72×10^-7
