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
levacccp [35]
3 years ago
7

What is the kinetic energy of an object moving 40m/s with a mass of 20kg?

Physics
1 answer:
Svet_ta [14]3 years ago
7 0
KE = (1/2) (mass) (speed)²

KE = (1/2) (20 kg) (40 m/s)²

KE = (1/2) (20 kg) (1,600 m²/s²)

KE = (10 kg) (1,600 m²/s²)

KE = 16,000 Joules
You might be interested in
Determine the total moment of inertia of a merry-go round with 5 children sitting on it. Of the five children, four are seated a
BaLLatris [955]

Answer:

Explanation:

Given that,

We have five children.

Each of mass m =30kg

They sit on a merry go round

Mass of Merry go round M= 150kg

Radius of Merry go round is r =2m

Four children sit at the edge of the merry go round but one child sit at the centre.

The four child that sit at the edge are 2m from the centre of the merry go round but the one at the centre is 0m from the centre

Moment of inertia?

Moment of inertia is given as

I=Σmi•ri²

For the question, the moment of inertia is the combination of inertial of child and the merry go round

I= I(merry go round) + I(four child)+ I(last child)

The merry go round is assumed to be a solid cylinder, so it is going to have the moment of inertia of solid cylinder

Then,

I(merry go round ) =½ Mr²

Also, Four of the child has the same moment of inertia, they are 2m form the centre of the merry go round why the last child has no moment of inertia

I= I(merry go round) + I(four child) +I(last child )

I= ½Mr² + 4mr² + mr'²

I = ½ × 150 ×2² + 4×30×2² + 30×0²

I = 300 +480+0

I = 780 kgm²

7 0
3 years ago
50 POINTS
strojnjashka [21]

Answer:   A    Answers. Assuming that the terminal velocity doesn't change during the fall, then the kinetic energy would remain constant. However the terminal velocity decreases during the fall since the air becomes denser at lower altitudes.

Explanation:

What happens to the KE of an object when it slows down and heats up? - Quora. The kinetic energy goes down and the loss of the kinetic energy is through the production of heat energy. In real world this is due to friction, or an opposing force that decelerates the object, or a combination of both.

8 0
3 years ago
Read 2 more answers
Calculate the separation between the two lowest levels for an O2 molecule in a one-dimensional container of length 5.0 cm. At wh
MariettaO [177]

Answer:

The separation between the two lowest levels =  1.24 * 10^{-39}J

The values of n where the energy of molecule reaches 1/2 kT at 300K = 2.2 * 10^{9}

The separation at this level = 1.8 * 10^{-30}J

Explanation:

Knowing the formula

En = \frac{n^{2} h^{2}  }{8 mL^{2} }

Mass of oxygen molecule

m (O2) = 32 amu * \frac{1.6605 * 10^{-27 kg} }{1 amu}

So the energy diference between the two lowest levels:

E2 - E1 = \frac{3h^{2} }{8mL^{2} }

E2 - E1 =  \frac{3 * (6.626 * 10^{-34} Js)^{2} } {8 * 32 amu * (\frac{1.6605 * 10^{-27 kg} }{1 amu})* (5*10^{-2})^{2}   } = 1.24 * 10^{-39}J

Now we should find n where the energy of molecule reaches 1/2 kT

En = \frac{n^{2} h^{2}  }{8 mL^{2} } = \frac{1}{2}kT

\frac{h^{2}  }{8 mL^{2} } = 4.13 * 10^{-14}J

n^{2} *  (4.13 * 10^{-14}J) = \frac{1}{2} (1.38 * 10^{-23}JK^{-1}) * 300K

n = 2.2 * 10^{9}

by the end is necessary to calculate the separation of the level

En - En-1 = (n^{2} - (n - 1)^{2}) * \frac{h^{2}  }{8 mL^{2} }

              = 1.8 * 10^{-30}J

4 0
3 years ago
Which activities demonstrate reaction time the most?
Black_prince [1.1K]

Answer:

A goal keepee catering the ball in time is answer

7 0
2 years ago
Help, please!!!!!<br> I just need help putting the vocab word in the box where it belongs.
Ber [7]

here's the first part but for the 2nd one all I know is that the word "compression" goes on the spirals that are closer together.

hope this helps!

8 0
2 years ago
Other questions:
  • Suppose you increase your walking speed from 5m/s to 15m/s in a period of 1 s. What is your acceleration?
    5·1 answer
  • 3
    12·1 answer
  • What is the pressure on a horizontal surface with an area of 8 msquared that is 4 m​ underwater? Use 1000 kg divided by m cubed
    7·1 answer
  • What is a substances specific heat
    8·2 answers
  • An electron falls through a distance d in a uniform electric field of magnitude E. Thereafter, the direction of the field is rev
    12·2 answers
  • Which liquid is the most viscous?<br><br> syrup<br> water<br> milk<br> apple juice
    8·2 answers
  • PLS HELP,WILL GIVE BRAINLIEST + 30 POINTS
    12·1 answer
  • Magnitude F have a
    7·1 answer
  • A jet starts from rest and accelerates to a speed of 100 m/s in 10 seconds before taking off. how far does it travel before taki
    15·2 answers
  • Running water has materials such as dirt, sand, and dead plants and animals in it. When this water ends up in a lake, the materi
    10·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!