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
Roman55 [17]
3 years ago
5

A car starts from rest and accelerates uniformly over a time of 18 seconds for a distance of 390 m. Determine the acceleration o

f the car.

Physics
1 answer:
Sergeeva-Olga [200]3 years ago
5 0

Answer:

a=2.4\ m/s^2

Explanation:

Given that,

The initial speed of a car, u = 0

Time, t = 18 s

Distance, d = 390 m

We need to find the acceleration of the car. Let it is a. Using the second equation of motion to find it.

d=ut+\dfrac{1}{2}at^2

or

d=\dfrac{1}{2}at^2\\\\a=\dfrac{2d}{t^2}\\\\a=\dfrac{2\times 390}{(18)^2}\\\\a=2.4\ m/s^2

So, the acceleration of the car is 2.4\ m/s^2.

You might be interested in
A 1100 kgkg safe is 2.4 mm above a heavy-duty spring when the rope holding the safe breaks. The safe hits the spring and compres
Drupady [299]

Answer:

191.36 N/m

Explanation:

From the question,

The Potential Energy of the safe = Energy of the spring when it was compressed.

mgh = 1/2ke²............... Equation 1

Where m = mass of the safe, g = acceleration due to gravity, h = height of the save above the heavy duty spring , k = spring constant, e = compression

Making k the subject of the equation,

k =2mgh/e²................ Equation 2

Given: m = 1100 kg, h = 2.4 mm = 0.0024 m, e = 0.52 m

Constant: g = 9.8 m/s²

Substitute into equation 2

k = 2(1100)(9.8)(0.0024)/0.52²

k = 51.744/0.2704

k = 191.36 N/m

Hence the spring constant of the heavy-duty spring = 191.36 N/m

3 0
2 years ago
A freight train rolls along a track with considerable momentum. If it were to roll at the same speed but had twice as much mass,
fomenos

Answer:

The momentum would be doubled

Explanation:

The magnitude of the momentum of the freight train is given by:

p=mv

where

m is the mass of the train

v is its speed

In this problem, we have that the speed of the train is unchanged, while the mass of the train is doubled:

m'=2m

therefore, the new momentum is

p'=m'v=(2m)v=2(mv)=2p

so, the momentum has also doubled.

7 0
3 years ago
Plants make food through photosynthesis, and photosynthesis takes place mostly in plant leaves, but when plants lose their leave
Nastasia [14]

Answer:

The answer is not B or D because they need light co2 and water to make their food so B and D are out. and unless someone is walking during winter to feed it. It will not be A so the answer is C.

Explanation:

3 0
3 years ago
What is the kinetic energy of a bicycle with a mass of 14 kg traveling at a<br> velocity of 3.0 m/s?
Sav [38]

46.6666 that is the mass number

Explanation:

14 divided 3.0

5 0
2 years ago
What happens to the iron in the coilgun if the electricity in the coil was turned on
Andrews [41]

  • <em><u>The piece of iron has become a magnet. Some substances can be magnetized by an electric current. When electricity runs through a coil of wire, it produces a magnetic field. The field around the coil will disappear, however, as soon as the electric current is turned off.</u></em>
7 0
2 years ago
Other questions:
  • Astronomers analyze starlight to determine a star’s (a) temperature; (b) composition; (c) motion; (d) all of the above.
    10·1 answer
  • What is the color of the stars with the highest surface temperature and what is the color of the stars with the lowest surface t
    9·2 answers
  • Suzie stands on a pedestal and touches the dome of a running Van de Graaf generator. In a few seconds she observes her hair stan
    9·2 answers
  • The reason an astronaut in an earth satellite feels weightless is thatThe reason an astronaut in an earth satellite feels weight
    11·2 answers
  • Which kinds of objects emit visible light in the electromagnetic spectrum?
    13·1 answer
  • He distance between two consecutive crests is 2.5 meters. Which characteristic of the wave does this distance represent? amplitu
    5·2 answers
  • How are energy and distance up the ramp related
    15·1 answer
  • In an experiment, a disk is set into motion such that it rotates with a constant angular speed. As the disk spins, a small spher
    7·1 answer
  • What is a scientific theory is and under what conditions a theory may be revised?
    13·1 answer
  • What is your independent variable? (Page 3 on Investigation)
    5·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!