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
Alexxx [7]
2 years ago
7

A year 11 pupil with a mass of 55kg swinging back on their chair and falling off it at a speed of 0.6m/s. What is his kinetic en

ergy?

Physics
1 answer:
posledela2 years ago
3 0

Answer:

Uk = 9.9 J

Explanation:

To calculate the kinetic energie (Uk), you can make use of this formula:

Uk = 0.5 * m * v²

given m = 55 kg and v = 0.6 m/s

Substituting in the formula gives:

Uk = 0.5 * 55 * (0.6)²

Uk = 0.5 * 55 * 0.36

Uk = 9.9 J

Extra:

Now let's examine the formula in relation to the SI units. <em>If you understand the following, it will give you great insight in how smart Phisics is inter twained by looking at formulas and their standard units. It will save you time in future to convert formulas, if you use the right standard units.</em>

The formula for kinetic energie is:

Uk = 0.5 * m * v²

Standard SI unit for mass m is kg.

Standard SI unit for speed v is m/s.

So v * v = v² and therefore v² must have the standard SI unit of m²/s².

From the formula, you see that the unit of Uk must be kg*m²/s² and since Uk is normally given in J, these both forms must be the same !

The main unit for Uk is the Joule. <em>Now</em><em> </em><em>please</em><em> </em><em>see</em><em> </em><em>the</em><em> </em><em>picture</em><em>,</em><em> </em><em>which</em><em> </em><em>shows</em><em> </em><em>the </em><em>relation</em><em> </em><em>between </em><em>the </em><em>J </em><em>and </em><em>other</em><em> SI units</em><em>.</em><em> </em><em>Please</em><em> </em><em>understand</em><em> </em><em>that</em><em> </em><em>you</em><em> </em><em>can</em><em> </em><em>construct</em><em> </em><em>your</em><em> </em><em>'own'</em><em> </em><em>formulas</em><em> </em><em>based</em><em> </em><em>these</em><em> </em><em>units</em><em>.</em><em> </em><em>Now</em><em> </em><em>here</em><em> </em><em>is</em><em> </em><em>the</em><em> </em><em>time</em><em> </em><em>saver</em><em>:</em>

Because almost always the right units are <em>given</em> in a question, or because sometimes you can look up a constant in a table with an exotic and seemingly complicated unit, but that says a lot about the formula which must have been some how involved!

<em>By this, I hope you now understand the implication of using the right standard SI units and how that can help you figure out what formula is needed.</em>

You might be interested in
What do you think we can learn about Earth's history by looking at the Grand Canyon?
viktelen [127]
We can look at all the ages of the earth since it’s a big crack is reveals many layers of the earth and we can know about chemicals and metals that were in earth and diffrent times
5 0
3 years ago
Imagine a sunny day at the pool. The sun is out and you are thinking about how the light travels from the sun and then hits the
Dovator [93]

Answer:

it evaporats

Explanation:

because the sun is so hot that the water will turn into gas hope i helped

5 0
3 years ago
Read 2 more answers
14. The design for a rotating spacecraft below consists of two rings. The outer ring with a radius of 30 m holds the living quar
Zolol [24]

Answer:

T= 11.0003s

Explanation:

From the question we are told that

The outer ring with a radius of 30 m

inner Gravity Approximately 9.80 m/s'

Outer Gravity Approximately 5.35 m/s.

Generally  the equation for centripetal force is given mathematically as

Centripetal acceleration enables Rotation therefore?

     \omega ^2 r =Angular\ acc

Considering the outer ring,

 \omega ^2 r = 9.8

  \omega ^2= \frac{9.8}{30}

 \omega = \sqrt{\frac{9.8}{30}}

 \omega= 0.571 rad/s

Therefore solving for  Period T

Generally the equation for solving Period T is mathematically given as

 T= \frac{2\pi}{\omega}

 T= \frac{2\pi}{0.571 rad/s}

 T= 11.0003s

5 0
3 years ago
Mary was looking out of the window she saw lightening and then heard thunder a few seconds later explain why she saw lightening
alekssr [168]

Explanation:

It is based upon the fact that " The light travels faster then sound." As the speed of light is faster then the speed of sound, light travels 300,000 km per second and sound travels 1192 km per hour. That is why we observe the lightening first and hear the the sound of thunder later.

        You can do this experiment by yourself. Once you see the lightening start counting the seconds until you hear the sound of thunder.Then divide the seconds by 5, you will find out how many miles away the lightening strike was.

3 0
3 years ago
A train traveled 100 kilometers north in 2 hours. After exchanging some railroad cars, it traveled 100 kilometers south in 2 hou
hodyreva [135]

Answer:Due to change in direction

Explanation:

Given

Initially train has traveled a 100 km in North and after exchanging some railroad cars, it traveled 100 in south.

The velocity of the train changes as it direction of motion changes. Velocity is the vector quantity which require direction and magnitude for its reperesentation.

7 0
2 years ago
Other questions:
  • A moving walkway at an airport has a speed v1 and a length l. a woman stands on the walkway as it moves from one end to the othe
    8·1 answer
  • Which phenomenon can only be explained by assuming that light is quantized
    8·1 answer
  • Someone please help me!
    8·1 answer
  • 4. A tankful of liquid has a volume<br>of 0.2m3. What is the volume in (a)<br>lities (b) cm3 (c)ml​
    6·1 answer
  • If the amount of gas in a sealed container increases, what happens to the pressure in the container
    10·2 answers
  • I need help with air resistance...
    15·1 answer
  • What do astonomers use to calculate the age of the universe
    12·1 answer
  • If Brandy ran for 3 seconds and ended up 6 meters away, what was her speed?
    8·2 answers
  • Which bone is located in the thigh or upper hind limb, articulating at the hip or knee?
    9·1 answer
  • a water wave has a speed of 23.0 meters/second. if the waves frequency is 0.0680 hertz, what is the wavelength
    6·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!