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
suter [353]
2 years ago
11

If a moving car speeds up until it is going twice as fast, how much kinetic energy doe s it have compared with its initial kinet

ic enegy
Physics
1 answer:
dezoksy [38]2 years ago
6 0
The kinetic energy of an object of mass m and velocity v is given by
K= \frac{1}{2} mv^2

Let's call v_i the initial speed of the car, so that its initial kinetic energy is
K_i =  \frac{1}{2} mv_i^2
where m is the mass of the car. 

The problem says that the car speeds up until its velocity is twice the original one, so 
v_f = 2 v_i
and by using the new velocity we can calculate the final kinetic energy of the car
K_f =  \frac{1}{2} mv_f^2 =  \frac{1}{2}m (2 v_i)^2 = 4 ( \frac{1}{2} mv_i^2)=4 K_i
so, if the velocity of the car is doubled, the new kinetic energy is 4 times the initial kinetic energy.
You might be interested in
The X-ray source Cygnus X-1 has a mass of at least 11 solar masses and a diameter of only about one-quarter the diameter of the
SOVA2 [1]

Answer:

Answer is It was deduced from the rate at which it glimmers.

Refer below.

Explanation:

The X-ray source Cygnus X-1 has a mass of at least 11 solar masses and a diameter of only about one-quarter the diameter of the Earth. With such a small diameter it must be a compact object, and with such a large mass it can't be a white dwarf or a neutron star, so a black hole is the only possibility remaining. The diameter of Cygnus X-1 found:

It was deduced from the rate at which it glimmers.

7 0
3 years ago
At what rate does gravity cause objects to accelerate at sea level on earth
VLD [36.1K]

The acceleration due to gravity on Earth is 9.8 m/s per second.

5 0
3 years ago
Why is acceleration of an object moving at a constant velocity always zero?
k0ka [10]

Answer:

If an object is moving with a constant velocity, then by definition it has zero acceleration. So there is no net force acting on the object. The total work done on the object is thus 0 (that's not to say that there isn't work done by individual forces on the object, but the sum is 0 ).

Explanation:

In the middle, when the object was changing position at a constant velocity, the acceleration was 0. This is because the object is no longer changing its velocity and is moving at a constant rate.

8 0
2 years ago
A motor running at 2600 rev/min is suddenly switched off and decelerates uniformly to rest after 10 s. Find the angular decelera
Mama L [17]
Angular acceleration = (change in angular speed) / (time for the change)

change in angular speed = (zero - 2,600 RPM)  =  -2,600 RPM

time for the change = 10 sec

Angular acceleration = -2600 RPM / 10 sec = -260 rev / min-sec

(-260 rev/min-sec) x (1 min / 60 sec) = <em>-(4 1/3)  rev / sec²</em>

Since the acceleration is negative, the motor is slowing down.
You might call that a 'deceleration' of (4 1/3) rev/sec² .

The average speed is  1/2(2,600 + 0) = 1,300 rev/min = (21 2/3) rev/sec.

Number of revs = (average speed) x (time) = (21 2/3) x (10sec) = <em>(216 2/3) revs</em>
6 0
3 years ago
describe an experiment to show how the frequency of a note emitted by a vibrating string depends on the tension of the string
mart [117]
Easy ! 

Take any musical instrument with strings ... a violin, a guitar, etc.

The length of the vibrating part of the strings doesn't change ...
it's the distance from the 'bridge' to the 'nut'.

Pluck any string.  Then, slightly twist the tuning peg for that string,
and pluck the string again.

Twisting the peg only changed the string's tension; the length
couldn't change.

-- If you twisted the peg in the direction that made the string slightly
tighter, then your second pluck had a higher pitch than your first one.

-- If you twisted the peg in the direction that made the string slightly
looser, then your second pluck had a lower pitch than the first one.
3 0
3 years ago
Other questions:
  • F = ma
    13·2 answers
  • A force is described by its BLANK and by the direction in which it acts
    15·1 answer
  • Researchers at the University of Georgia have evaluated trends in streamside forests in areas within roughly 400 feet of the sta
    15·1 answer
  • A force that results from charged particles is called?
    14·2 answers
  • what is the the wavelength if a wave cycles up and down three times per second and the distance between each wave is 1.7m?
    13·1 answer
  • An Alaskan rescue plane traveling 49 m/s
    6·1 answer
  • 1)
    15·1 answer
  • In a physics lab, a 0.500-kg cart (Cart A) moving with a speed of 129 cm/s encounters a magnetic collision with a 1.50-kg cart (
    5·1 answer
  • The box set was an important because:
    6·2 answers
  • -x times -x what is the answer​
    12·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!