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
MrRissso [65]
4 years ago
5

An athlete completes one round of a circular track of diameter 200 m in 40 s. What will be the distance covered and the displace

ment at the end of 2 minutes 20 s?
Physics
1 answer:
Zepler [3.9K]4 years ago
5 0

Answer:

Explanation:

Displacement is the shortest distance possible between initial and final position.

As the athlete is in circular motion , displacement is zero. [ THis is because , the initial and final position is the same ]

Distance covered in 1 round = Circumference of the circle

Circumference of the circle = 2πr

Diameter = 200 m

Radius = 100 m

Distance covered in 1 round[ 40 sec ] = 2 × 22/7 × 100 = 628.57 m

Distance covered in 1 sec = 628.57 ÷ 40 = 15.71 m

2min 20 sec = 140 sec

Distance covered in 140 sec = 15.71 × 140 = 2199.4 m

For each complete round the displacement is zero. Therefore for 3 complete rounds, the displacement will be zero.

At the end of his motion, the athlete will be in the diametrically opposite position. That is, displacement = diameter = 200 m.

Hence, the distance covered is 2200 m and the displacement is 200 m.

You might be interested in
A torque of 50 N*m acts on a wheel of moment of inertia 25 kg*m^2 for 4 s and then is removed.
motikmotik
You have to find the calculate<span> the circumference first then you can just multiply the diameter by π, which is about 3.142. That gives you the distance for each </span>revolution<span>. Then you can multiply by the </span>number of revolutions<span> per minute.

</span>
3 0
3 years ago
Which of the following would be used in luminosity calculations?
Daniel [21]

Answer:

1) joule

2) kgm^{2}/s^{2}

3) 10\%

Explanation:

1) Luminosity is the <u>amount of light emitted</u> (measured in Joule) by an object in a unit of<u> time</u> (measured in seconds). Hence in SI units luminosity is expressed as joules per second (\frac{J}{s}), which is equal to Watts (W).

This amount of light emitted is also called radiated electromagnetic power, and when this is measured in relation with time, the result is also called radiant power emitted by a light-emitting object.

Therefore, if we want to calculate luminosity the Joule as a unit will be used.

2) Work W is expressed as force  F multiplied by the distane  d :

W=F.d

Where force has units of  kgm/s^{2} and distance units of m.

If we input the units we will have:

W=(kgm/s^{2})(m)

W=kgm^{2}/s^{2}  This is 1Joule (1 J) in the SI system, which is also equal to 1 Nm

3) The formula to calculate the percent error is:

\% error=\frac{|V_{exp}-V_{acc}|}{V_{acc}} 100\%

Where:

V_{exp}=7.34 (10)^{-11} Nm^{2}/kg^{2} is the experimental value

V_{acc}=6.67 (10)^{-11} Nm^{2}/kg^{2} is the accepted value

\% error=\frac{|7.34 (10)^{-11} Nm^{2}/kg^{2}-6.67 (10)^{-11} Nm^{2}/kg^{2}|}{6.67 (10)^{-11} Nm^{2}/kg^{2}} 100\%

\% error=10.04\% \approx 10\% This is the percent error

8 0
4 years ago
Whats the answer<br> ----------------------------
GenaCL600 [577]

Answer:

repel each other

Explanation:

The magnitude of the charge of an electron is called... ... If a positively-charged glass rod is suspended so that it turns easily and another positively-charged glass rod is brought close to it, the two rods will... Repel each other.

8 0
3 years ago
A group of scientists have obtained some experimental results.
topjm [15]
<span>In order best to find out whether the obtained experimental results are worth mor etime and resources the group of scientists should present their results (could be done also in poster session) to other scientists in order to hear their opinion and get a feedback. The shoudl also ask another researchers to redo the experiments and to compare the results. </span>
4 0
3 years ago
Read 2 more answers
How can i calculate distances between objects by using the concepts of echo location
dangina [55]
Send wave from your location to the object and wait until echo is back.
Measure the time taken.

If you know the speed of wave (say sound wave), than just multiply by half time taken wave to return
5 0
3 years ago
Other questions:
  • A student went to a hill station early in the morning, he could hear the echo of his clap after 0.1 second. When he went to the
    10·1 answer
  • In a local diner, a customer slides an empty coffee cup down the counter for a refill. The cup slides off the counter and strike
    12·1 answer
  • if you look inside the bowl of a shiny metal spoon, your image is upside down. if you look at the outside of the bowl, your imag
    7·1 answer
  • Can some one pls give me the knowns and unknowns , formula and answer for question 4,5,6
    12·1 answer
  • The management information base (MIB) is a repository of data maintained at a managing entity site, providing the network manage
    6·1 answer
  • Select the correct answer. Five marbles roll down a ramp. Each marble reaches the bottom of the ramp at a speed of 3 meters/seco
    9·2 answers
  • Which statement will be true if you increase the frequency of a periodic wave?
    8·2 answers
  • Which of the following statements are true about metallic bonds? A. Metallic bonds hold together atoms with somewhat similar ele
    15·1 answer
  • A copper wire has a circular cross section with a radius of 1.00 mm. (a) If the wire carries a current of 2.80 A, find the drift
    7·1 answer
  • The Pioneer 10 spacecraft was launched in March 1972 to explore the solar system. Pioneer 10 has continued on its journey and is
    8·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!