1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
julia-pushkina [17]
3 years ago
8

You are driving downhill on a rural road with a 3% grade at a speed of 45 mph. While playing on the side of the road, a child ac

cidentally runs onto the roadway to pick up a ball. At what distance you must first see the child to stop your vehicle before reaching the child? How would this distance be different if you were driving on the same road and at the same speed, but going uphill? Use t
Physics
1 answer:
Dennis_Churaev [7]3 years ago
5 0

Answer: a) 95.07m b) 81.88 m

Explanation:

a)

For finding the distance when vehicle is going downhill we have the formula as:

Stop sight distance= Velocity*Reaction time + Velocity² / 2*g*(f constant- Grade value)

Now by AASHTO, we have for v= 45 mph= 72.4 kph, f= 0.31

Reaction time= 0.28

So putting values we get

Stop sight distance= 0.28*72.4 *1  + \frac{(0.28*72.4)^{2} }{2*9.81*(0.31-0.03)}

Stop sight distance= 95.07 m

b)

For finding the distance when vehicle is going uphill we have the formula as:

Stop sight distance= Velocity*Reaction time + Velocity² / 2*g*(f constant- Grade value)

Now by AASHTO, we have for v= 45 mph= 72.4 kph, f= 0.31

Reaction time= 0.28

So putting values we get

Stop sight distance= 0.28*72.4 *1  + \frac{(0.28*72.4)^{2} }{2*9.81*(0.31+0.03)}

Stop sight distance= 81.88 m

You might be interested in
The rate an object is moving relative to a reference point is its
natulia [17]

Velocity is an object's rate of change (usually over time) of its displacement.

5 0
2 years ago
Shrill sound is of -------------- *
Leona [35]

Answer:

Higher frequency.

Explanation:

Sound are mechanical waves that are highly dependent on matter for their propagation and transmission.

Sound travels faster through solids than it does through either liquids or gases. A student could verify this statement by measuring the time required for sound to travel a set distance through a solid, a liquid, and a gas.

Mathematically, the speed of a sound is given by the formula:

Speed = wavelength * frequency

Generally, the frequency of a sound wave determines the pitch of the sound that would be heard.

A shrill sound refers to a type of sound that is typically sharp, high pitched and as such has higher frequency.

Hence, shrill sound is of higher frequency.

6 0
2 years ago
The aorta is approximately 25 mm in diameter. The mean pressure there is about 100 mmHg and the blood flows through the aorta at
Ksenya-84 [330]

Answer:

Explanation:

25 mm diameter

r₁  = 12.5 x 10⁻³ m radius.

cross sectional area =  a₁

Pressure P₁  = 100 x 10⁻³ x 13.6 x 9.8 Pa

a )

velocity of blood v₁ = .6 m /s

Cross sectional area at blockade = 3/4 a₁

Velocity at blockade area = v₂

As liquid is in-compressible

a₁v₁ = a₂v₂

a₁ x .6 m /s  = 3/4 a₁ v₂

v₂ = .8m/s

b )

Applying Bernauli's theorem formula

P₁ + 1/2 ρv₁² =  P₂ +  1/2 ρv₂²

100 x 10⁻³ x 13.6 x10³x 9.8 + 1/2 X 1060 x .6² = P₂ +  1/2x 1060 x .8²

13328 +190.8 = P₂ + 339.2

P₂ = 13179.6 Pa

= 13179 / 13.6 x 10³ x 9.8 m of Hg

P₂ =  .09888 m of Hg

98.88 mm of Hg

8 0
3 years ago
The velocity of sound on a particular day outside is 331 meters/second. What is the frequency of a tone if it has a wavelength o
Levart [38]
I think c hope it help

3 0
3 years ago
Read 2 more answers
Como estan formados los musculos?
VikaD [51]

Answer:

Explanation: El músculo esquelético está formado por fibras musculares, rodeadas de una capa de tejido conjuntivo, denominada endomisio. Las fibras se reúnen en fascículos primarios, que también están rodeados por otra capa de tejido conjuntivo, esta vez, más grueso, denominada perimisio.

3 0
2 years ago
Read 2 more answers
Other questions:
  • Venus has about the same mass as Earth and is about the same distance from the Sun. Yet Venus does not support life. An importan
    13·2 answers
  • An amoeba is a one-celled protist. Amoeba contain all the organelles of a typical eukaryotic animal cell. It is a heterotroph an
    10·1 answer
  • In chemistry class, you are given 3 liquids: Liquid A, Liquid B, and Liquid C. They are each in their own beaker. One of these l
    9·1 answer
  • A water heater that has the shape of a right cylindrical tank with a radius of 1 foot and a height of 4 feet is being drained. h
    14·1 answer
  • The gas law for a fixed mass m of an ideal gas at absolute temperature T, pressure P, and volume V is PV=mRT, where R is the gas
    10·1 answer
  • How much force is required to accelerate a 50 kg mass at 2 m/s2?
    6·1 answer
  • LIULIS.<br> What would happen to speed if distance increased in the same amount of time?
    14·1 answer
  • A car travels 1000 meters in 5 seconds. What is its average velocity?
    8·2 answers
  • Two gliders collide on an air track. Glider 1 has a mass of 7.0 kg, and glider 2 has a mass of 4.0 kg. Before the collision, gli
    10·1 answer
  • Givereasons for the following.
    13·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!