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
If a canadian plane is traveling at 500 miles/hr, how fast is this in m/s?
patriot [66]
223.52 meters per second
6 0
3 years ago
According to the principal of wave refraction, when light from the atmosphere enters a medium of greater density at an oblique a
Hoochie [10]

Answer:

d. velocity slows down and angle changes

Explanation:

6 0
2 years ago
6. A wave has a frequency of 600 Hz and is traveling at 300 m/s. What is its<br> wavelength?
Luda [366]

Answer:

0.5m

Explanation:

v=f×lamda

v is 300m/s, f is 600Hz, lamda is ?

lamda=v/f

lamda=300/600

lamda =3/6=1/2m

5 0
2 years ago
Ask Your Teacher The height h in feet reached by a dolphin t seconds after breaking the surface of the water is given by h = −16
kirza4 [7]

Answer:

1 second

Explanation:

h = −16t² + 32t

When, h = 16

16 = −16t² + 32t

Divide each of the numbers by 16

1 = -1t² + 2t

Rearrange the equation

1t²-2t+1 = 0

Solving by the quadratic formula, we get

t=\frac{-(-2)\pm \sqrt{(-2)^2-4\times 1\times 1}}{2\times 1}\\\Rightarrow t=\frac{2\pm 0}{2}\\\Rightarrow t=1\ s

So, time taken by the dolphin to jump out of the water and touch the trainer's hand is 1 second.

3 0
3 years ago
A 81 kg person sits on a 3.8 kg chair. Each leg of the chair makes contact with the floor in a circle that is 1.2 cm in diameter
tankabanditka [31]

Answer:

1.9 MPa

Explanation:

Mass of person = 81 kg

Mass of chair = 3.8 kg

Diameter of contact point = 1.2 cm = D

Radius of contact point = 1.2/2 = 0.6 cm

Total mass of chair and person = 81 + 3.8 = 84.8 kg = M

Acceleration due to gravity = 9.81 m/s²

Force acting on the floor

<em>F = Mg</em>

<em>⇒F = 84.8×9.81</em>

<em>⇒F = 831.888 N</em>

Area of the contact point

<em>A = πR²</em>

<em>⇒A = π0.006²</em>

<em>⇒A = π0.000036 m²</em>

Area of the four points is

<em>4A = 0.000144π m²</em>

Pressure

p=\frac{F}{A}\\\Rightarrow p=\frac{831.888}{0.000144\pi}\\\Rightarrow p=1838876.21\ Pa=1.83887621\times 10^6\ Pa=1.9 MPa

Pressure exerted on the floor by each leg of the chair is 1.9 MPa

5 0
3 years ago
Other questions:
  • Find the magnitude of vector A = i - 2j + 3k O V14 10 O4
    7·1 answer
  • If I move 15ft foward, 15 ft backwards, 15 ft to the right, 15ft to the left where am I?
    7·2 answers
  • Vaccine ASAP don't got much time
    8·2 answers
  • What type of acceleration does an object moving in a circular path with constant speed experience?
    11·2 answers
  • A skater with a mass of 72 kg is traveling east at 5.8 m/s when he collides with another skater of mass 45 kg heading 60° south
    5·1 answer
  • Why were you able to see the effects of the magnetic fields using iron filings
    10·2 answers
  • Jenna flips a 10p coin four times. Here are her results:
    10·1 answer
  • A 2-kg object is moving at 3 m/s. A 4-N force is applied in the direction of motion and if the object has a final velocity 7m/s.
    10·1 answer
  • Describe how body composition is measured?​
    6·1 answer
  • A dockworker applies a constant horizontal force of 80.0 N to a block of ice on a smooth horizontal floor. The frictional force
    8·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!