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
Mashutka [201]
3 years ago
9

You're driving down the highway late one night at 20 m/s when a deer steps onto the road 49 m in front of you. You reaction time

before stepping on the brakes is 0.50 s, and the maximum deceleration of your car is 10m/s2.
a. How much distance is between you and the deer when you come to a stop?
b. What is the maximum speed you could have and still not hit the deer?
Physics
1 answer:
Leno4ka [110]3 years ago
4 0

Answer:

v = 26.7 m/s

Explanation:

Given,

speed of the car = 20 m/s

distance between the car and the deer = 49 m

time taken to press the brake = 0.50 s

maximum deceleration of the car = 10 m/s²

Now,

distance travel by the car in 0.5 s = u x t = 20 x 0.5 = 10 m

distance travel by the car after the break is pressed

Using equation of motion

v² = u² + 2 a s

0² = 20² - 2 x 10 x s

s = 20 m

Total distance travel by the car = 20 + 10 = 30 m

Distance between deer and car = 49-30 = 19 m.

b. Maximum speed a car could have

Distance travel by the car in reaction time = v' x 0.5

v' is the maximum speed of the car.

maximum distance car can cover = 49 - 0.5 v'

Now, Using equation of motion

v² = u² + 2 a s

0² =v'² - 2 x 10 x (49- 0.5 x v')

v'² +10 v' -980 = 0

By solving

v = 26.7 m/s

Hence, maximum speed of the car can be 26.7 m/s

 

You might be interested in
A client experiences difficulty in performing the prone iso-abs exercise. Which of the following should be suggested as an regre
butalik [34]

Answer:

a. Quadruped arm and opposite leg raise

Explanation:

Quadruped arm and opposite leg lift

- Kneel on the floor, lean forward and place your hands down.

- Keep your knees in line with your hips and hands directly under your shoulders.

- Simultaneously raise one arm and extend the opposite leg, so that they are in line with the spine.

- Go back to the starting position.

This method is usually used as an alternative to iso-abs exercise or also known as a bridge, which allows you to exercise the abdominal and spinal area at the same time.

It is also used together with other exercises for the treatment of hyperlordosis.

8 0
3 years ago
How do you reduce friction
choli [55]
To reduce friction between two surfaces, you have to
make the surfaces smoother. 

The best way to do that is to introduce a fluid between them,
like grease, oil, or air.
3 0
3 years ago
Signment
jeka94

Answer:

v = 5.15 m/s

Explanation:

At constant velocity, the cable tension will equal the car weight of 984(9.81) = 9,653 N

As the cable tension is less than this value, the car must be accelerating downward.

7730 = 984(9.81 - a)

a = 1.95 m/s²

kinematic equations s = ut + ½at² and v = u + at

-5.00 = u(4.00) + ½(-1.95)4.00²

u = 2.65 m/s    the car's initial velocity was upward at 2.65 m/s

v = 2.65 + (-1.95)(4.00)

v = -5.15 m/s

3 0
3 years ago
Wood is an example of a fossil fuel.
nexus9112 [7]
A.kinetic energy for it an example of wood.
6 0
3 years ago
Which is not expecting acceleration?
Kamila [148]

1. Answer: A skydiver whose air resistance is equal to that of her weight.

A skydiver free falls under gravity but her rate of fall slows down due to drag -air resistance. when this air resistance becomes equal to her weight, the two get balanced and the body does not accelerate or decelerates.

2. Answer: Gravity

Contact forces are those which act when there is physical contact between two bodies. For example: normal force, tension and spring force.

Non-contact forces act between two bodies even when they are at a distance apart. For example: gravity, electric force, magnetic force etc.

3. Answer: The tendency of an object's motion to remain the same.

Inertia is a property of matter by virtue of which it tends to remain in its state of motion or rest. It does depend on mass of the object, more the mass, more is inertia. For example, cycle can be easily moved but we need real push hard for a car to move.

4. Answer: 254 N

The man pushes the box with 310 N force at an angle of  55 degrees to the horizontal.

we can write this in terms of horizontal (F cos \theta)and vertical component (F sin\theta).

Horizontal component: F_H=310 \times cos (55^o)= 178 N

Vertical component: F_v=310 \times sin (55^o)= 254 N

The vertical component would act towards the floor making the job more difficult to move the job.



7 0
3 years ago
Other questions:
  • Which part of the ear sends a message to the brain that is recognized as sound?
    14·1 answer
  • A child rides her bike at a rate of 12.0 km/hr down the street. A squirrel suddenly runs in front of her so she applies the brak
    6·2 answers
  • Why would genetic material need to be able to reproduce
    15·1 answer
  • In a circuit, electrons flow from _____ terminal to the ____ terminal.​
    9·1 answer
  • Would the springs inside a bathroom scale be more compressed or less compressed if you weighed yourself in an elevator that acce
    12·1 answer
  • The stored energy in a piece of coal can be _________ into heat energy.
    6·2 answers
  • What will the stopping distance be for a 2,000-kg car if -2,000 N of force are applied when the car is traveling 20 m/s?
    15·2 answers
  • What structure is used to focus light in a reflecting telescope?
    11·1 answer
  • A cyclist and his bicycle have a combined mass of 85 kg. If he is moving at
    15·1 answer
  • What is Doppler effect<br><br>​
    10·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!