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
Oduvanchick [21]
4 years ago
6

A car travelling at a constant speed of 70km/h passes a stationary police car. The police car immediately goes on the chase acce

lerating uniformly to reach a speed of 85km/h in 10s and continues at that speed until it overtakes the other car. Calculate the time taken for the police car to overtake the car?
Physics
1 answer:
Virty [35]4 years ago
5 0

Answer:

18.24 seconds

Explanation:

First you convert the km/h to m/s, 70km/h=(175/9)m/s,85km/h=(425/18)m/s.

You know it took 10 seconds for the police to reach 85 km/h. Calculate the distance that the car is ahead of the police (175/9)*10=1750/9m. Then by divide 1750/9 with 425/18, you will get the value 8.24. Add the 10 seconds with the 8.24 you will get 18.24 sec which is the total time.

You might be interested in
Que es el ecosistema de los animales
Gnom [1K]
<span>¿Qué estás pidiendo en esta situación. Hay entornos de diferencia de los animales. Algunos viven en entornos de tundra, otra veraniega en vivo, ambientes cálidos.</span>
5 0
3 years ago
A particular roller coaster has a mass of 3500 kg, a height of 4.0 m, and a velocity of 12 m/s. What is the kinetic energy? If n
Alenkinab [10]

Explanation:

given

m=3500kg,h=4.0m,v=12m/s

ke=½mv²

½×3500×12²=3500×144÷2

=252,000j or 252j

8 0
2 years ago
10. A frog leaps from its resting position at the
lana [24]

Answer:

The answer is C

Explanation:

F = m × a

m = 0.5kg

a = 3m/s²

F = 0.5 × 3

= 1.5N

5 0
3 years ago
A 6 kilogram block in outer space is moving at -100 m/s (to the left). It suddenly experiences three forces as shown below.
Alika [10]

Newton's second law and the kinematic relations allow to find the results for the questions about forces and the movement of the block are:

    B) the force applied to maintain the system is equilibrium is: F = 0.39 N with an angle of tea = 180º

    C) The maximum force is: F = 24 N

    D) The time to stop the block is: t = 25 s

 

Newton's second law establishes a relationship between the net force, the mass, and the acceleration of the body. In the special case that the acceleration is zero it is called the equilibrium condition.

B) They indicate a diagram of forces on the block, let's look for the components of the force that the block maintains with zero acceleration, in the attached we have a free-body diagram including the force applied to keep the system in equilibrium.

x-axis

      -10 + 12 sin 60 + Fₓ = 0

        Fₓ = 10- 12 sin 60 = -0.39 N

y-axis

       12 cos 60 - 6 + F_y = 0

        F_y = 6 - 12 cos 60 = 0 N

We can give the result of the force in two ways:

  • Form of coordinates F = -0.39 i ^ N
  • Form of module and angle.

Let's use Pythagoras' theorem to find the modulus.

       F = \sqrt{F_x^2 + F_y^2 } \\F = \sqrt{0.39^2 +0^2}  

       F = 0.39N

We use trigonometry for the angle.

       tan \theta = \frac{F_y}{F_x}

       tan θ=  0º

The component of the force is negative therefore this angle is in the second quadrant, to measure the angle from the positive side of the x axis in a counterclockwise direction.

        θ = 180 + θ'

        θ = 180 + 0

        θ = 180º

C) if the three forces can be moved and the maximum force occurs when they are all linear.

          10+ 6 + 6 + F = 0

          F = -24 N

D) if we maintain this force and eliminate the other three, the block stops, let's look for its acceleration.

          a = \frac{F}{m}  

          a = \frac{24}{6}  

         a =  4 m / s²

The acceleration is in the opposite direction of the initial velocity of the block v₀ = -100 m / s

If we use kinematic relations.

        v = v₀ - a t

Final velocity when stopped is zero

         t = \frac{0-v_o}{a}

         t = 100/4

         t = 25 s

In conclusion using Newton's second law and the kinematics relations we can find the results for the questions about the forces and the motion of the block are:

    B) the force applied to maintain the system is equilibrium is: F = 0.39 N with an angle of tea = 180º

    C) The maximum force is: F = 24 N

    D) The time to stop the block is: t = 25 s

Learn more about Newton's second law here: brainly.com/question/25545050

3 0
3 years ago
How could you test the hypothesis that elephants interpreted the ground signal as being farther away than the air signal?
bekas [8.4K]

Answer:

One way to test the hypothesis is to create two waves, one in the air and one on the ground at the same time. One of them for the elephant to get closer and another for the elephants to move away. Observe the reaction of the animal and with this we know which sound came first.

Explanation:

This hypothesis is based on the fact that the speed of sound in air is v = 343 m / s with a small variation with temperature.

The speed of sound in solid soil is an average of the speed of its constituent media, giving values ​​between

 wood      3900 m / s

 concrete 4000 m / s

 fabrics     1540 m / s

 earth       5000 m / s wave S

 ground    7000 m / s P wave

 

we can see that the speed on solid earth is an order of magnitude greater than in air.

One way to test the hypothesis is to create two waves, one in the air and one on the ground at the same time. One of them for the elephant to get closer and another for the elephants to move away. Observe the reaction of the animal and with this we know which sound came first.

From the initial information, the wave going through the ground should arrive first.

3 0
4 years ago
Other questions:
  • What are the four factors that influence how fast the water will flow
    10·1 answer
  • A car traveling at 24 m/s starts to decelerate steadily. It comes to a complete stop in 8 seconds. What is its acceleration?
    11·1 answer
  • Astronauts in orbit feel weightless because...
    7·2 answers
  • 15. A volleyball player who weighs 650 Newtons jumps 0.500 meters vertically off the floor. What is her kinetic energy just befo
    14·1 answer
  • “Is there a relationship between mass and gravity of a planet?” If there is a relationship, (such as- as the mass gets bigger th
    5·1 answer
  • A 2.0 kg mass is lifted 4.0 m above the ground. find the change in gravitational energy
    11·1 answer
  • Imagine a girl climbing a rope ladder to ride a zip line. It takes effort for her to get to the top of the ladder, but then she
    5·2 answers
  • "1. Which properties make a metal a good material to use for electrical wires? (1 poi
    7·1 answer
  • An egg is Free Falling Down from a nest in a tree (neglect air resistance)​
    11·1 answer
  • Does gravitational potential energy increase when getting closer to planet universal gravitation law.
    13·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!