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
Natalija [7]
3 years ago
11

Stopping distance of vehicles When brakes are applied to a moving vehicle, the distance it travels before stopping is called sto

pping distance. It is an important factor for road safety and depends on the initial velocity (v0) and the braking capacity, or deceleration that is caused by braking. A car travelling at speed 72km/hr suddenly applies the brake with the deceleration of 5m/s2. Find the stopping distance of the car.
Physics
1 answer:
DochEvi [55]3 years ago
7 0

Answer:

Stopping distance = 40m

Explanation:

Given the following :

Initial speed of vehicle before applying brakes = 72km/hr

Converting km/hr to m/s:

72km/hr = [(72 * 1000)m] / (60 * 60)

72km/hr = 72,000m / 3600s

72km/hr = 20m/s

Deceleration after applying brakes (-a) (negative acceleration) = - 5m/s^2

From the 3rd equation of motion:

v^2 = u^2 + 2as

Where v = final Velocity ; u= Initial Velocity ; a = acceleration and s = distance

Final velocity when the car stops will be 0

Therefore ;

v^2 = u^2 + 2as

0 = 20^2 + 2(-5)(s)

0 = 400 - 10s

10s = 400

s = 400/10

s = 40m

Therefore, the stopping distance of the car = 40 meters

You might be interested in
2. A rock is dropped off a bridge. How fast is the rock
zhenek [66]

Answer:

a) The velocity of rock at 1 second, v = 9.8 m/s

b) The velocity of rock at 3 second,  v = 29.4 m/s

c) The velocity of rock at 5.5 second,  v = 53.9 m/s

Explanation:

Given data,

The rock is dropped from a bridge.

The initial velocity of the rock, u = 0

a) The velocity of rock at 1 second,

   Using the first equation of motion

                         v = u + gt

                         v = 0 + 9.8 x 1

                          v = 9.8 m/s

b) The velocity of rock at 3 second,

                         v = u + gt

                         v = 0 + 9.8 x 3

                          v = 29.4 m/s

c) The velocity of rock at 5.5 second,

                         v = u + gt

                         v = 0 + 9.8 x 5.5

                         v = 53.9 m/s

5 0
3 years ago
the amount of water returning to the earth through precipitation is blank the amount of water leaving the earth through evaporat
nalin [4]

<u>Answer:</u>

<em>The amount of water entering the earth through precipitation is equal to the amount of water leaving earth through transpiration.</em>

<u>Explanation:</u>

Rates of precipitation and evaporation vary widely according to regions and seasons. But in a global scale the rates are equal. Thus the total amount of earth’s water maintains its constancy even though there is a continuous change in forms of water.

Evaporation and transpiration are the forms in which Water leaves the earth and it returns to the earth in various forms of precipitation like rain, snow, dew, fog etc. This water then reaches ocean and land. The water that reaches the land flows as surface run off into rivers and water bodies or seep into the ground replenishing the ground water table.

5 0
3 years ago
If you know what a JW is LET ME KNOW and it is a type of ppl
lisabon 2012 [21]

Answer:

only thing I think of when I see that is 'Just Wondering'

Explanation:

3 0
3 years ago
Read 2 more answers
A student jumps off a sled toward the NORTH after it stops at the bottom of an icy hill. Based on Newton's third law of motion,
zhuklara [117]

When the student the sled jumps off toward the north , the sled most likely move towards the south.

<h3>What is the Newton third law?</h3>

According to the Newton third law of motion, action and reaction are equal and opposite. This means that the direction of the reaction force must also be opposite to that of the action.

As such, when the student the sled jumps off toward the north , the sled most likely move towards the south.

Learn more about Newton third law:brainly.com/question/974124

#SPJ1

8 0
2 years ago
A 0.25 kg skeet (clay target) is fired at an angle of 30 degrees to the horizon with a speed of 25 m/s. When it reaches the maxi
kozerog [31]

Answer:

6.51 m and 37.13 m

Explanation:

from the question we were given

mass of skeet = 0.25 kg

speed of skeet = 25 m/s

angle = 30 degrees to the horizon

mass of pellet = 15 g

speed of pellet = 2000 m/s

without being hit by the pellet, the x and y components of the skeet velocity are  

Vx = 25 cos 30 = 21.65

Vy = 25 sin 30 = 12.5

now

V = U + (a x t)

where V = final velocity, U = initial velocity , a = acceleration, t = time and s = distance

-25 sin 30 = 25 sin 30 + (-9.8 x t)

-12.5 = 12.5 - 9.8 t

t = 2.55 s

also

V^2 = U^2 + 2as  ( s = vertical distance and V = 0 )

0 = (25 sin 30)^2 + 2 x (-9.8) x Y

19.6 Y = 156.25

Y =7.97 m

the distance traveled without the pellet hitting the skeet can be gotten using distance = speed x time

distance = 21.65 x 2.55 = 55.2 m

applying the conservation of linear momentum

on the x axis : (Ms x Us) + (Mp x Up) = (Ms x Vx) + (Mp x Vx)  ...equation 1

on the y axis :   (Ms x Us) + (Mp x Up) = (Ms x Vy) + (Mp x Vy) ...equation 2

(0.25 x 25 cos 30) + 0 = (0.25 +0.015) Vx

 Vx = 20.42m/s

0 + (0.015 x 200) = (0.25 + 0.015) Vy

 Vy = 11.32 m/s

now V^2 = U^2 + 2 as

 0 = 11.3^2 + (2 x (-9.8) x s)

s = 6.51 m                          

  • to find the extra distance moved after collision we apply

s = ut + 1/2 at^2

-7.98 = 11.32t + 1/2 (-9.8) t^2

4.9 t^2 - 11.32t + 7.98

t =  3.17 s

recall that distance = speed x time

distance = 20.42 x 3.17 = 64.73 m

the distance of the skeet before being hit would be half of the distance it travels without being hit, this is because the skeet was hit at its maximum height = 55.2 /2

= 27.6 m

therefore the extra distance traveled would be the change in distance = 64.73 -27.6 = 37.13 m

5 0
3 years ago
Other questions:
  • Are we even real? Do we exist or are we robots or a simulation or experiment?
    14·2 answers
  • A 0.400 kg bead slides on a straight frictionless wire and moves with a velocity of 3.50 cm/s to the right, as shown below. The
    11·1 answer
  • What is the relationship between energy use and motion?
    5·1 answer
  • 1. A 2.10 m rope attaches a tire to an overhanging tree limb. A girl swinging on the
    8·1 answer
  • Dillion takes a bottle of oil and vinegar salad dressing​
    9·1 answer
  • Consider the flask apparatus below, which contains 2.00 L of H2 at a pressure of 353 torr and 1.00 L of N2 at an unknown pressur
    15·2 answers
  • Colossal Cave was formed years ago by underground running water. Today, it is the home to many animals, like bats. These interac
    7·1 answer
  • What is the relationship between DNA and RNA?
    9·1 answer
  • Which of the following is an ozone depleting substance (ODS)?
    11·1 answer
  • A labor push a crate through 12m and 720 J of work .The magnitude of force was
    5·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!