D because the tornado siren are supposed to be loud so everyone could hear
Answer:2.103 m/s
Explanation:
Given
mass of sports car
mass of SUV
Suppose u is the velocity if sports car before collision
Conserving momentum we get
After collision the combined mass drag 2.8 m and finally stops
From work energy theorem work done by friction is equal to change in kinetic energy of the combined mass system
where
Initial velocity
Answer:
x_total = 20m
Explanation:
This is an exercise in kinematics, we will look for the distance it travels during the reaction time, where there is no braking, and then the distance during the deceleration.
Distance traveled during response time
v = x₁ / t
x₁ = v t
let's calculate
x₁ = 10 0.75
x₁ = 7.5 m
Now we calculate the distance during braking, the final speed is zero (v = 0)
v² = v₀² - 2 a x₂
x₂ = v₀² / 2 a
let's calculate
x₂ = 10² / (2 4)
x₂ = 12.5m
the total stopping distance is
x_total = x₁ + x₂
X_total = 7.5 + 12.5
x_total = 20m
Answer:
A. The upward pressure gradient force is balanced by gravity.
Explanation:
A. is correct because the pressure difference is actually generated by gravity. As in the following formula for the pressure at different points:
where are the pressure at 2 points, ρ is the density of the fluid, g is the gravitational constant, and h is the height difference.
B is incorrect because friction in air is too small to make an effect.
C is incorrect because the Coriolis force is horizontal, not vertical.
D is incorrect because a difference of 500 hPa = 50000 Pa, this is half of the atmospheric pressure.
E is incorrect because temperature cannot generate force.