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
KiRa [710]
3 years ago
15

An athlete at the gym holds a 2.5 kg steel ball in his hand. His arm is 70 cm long and has a mass of 4.0 kg.

Physics
1 answer:
aleksandr82 [10.1K]3 years ago
6 0

Answer:

B

Explanation:

Yea

You might be interested in
Two small stereo speakers are driven in step by the same variable-frequency oscillator. Their sound is picked up by a microphone
anygoal [31]

Answer:

The fundamental frequency at which the sound of speakers at the microphone produce constructive interference is 801.076458 Hz

Explanation:

For a given arrangement having constructive interference, we have;

R₁ - R₂ = 2·x = 0 + n·λ

The distance from one speaker to the microphone. R₁ = 4.50 m

The distance between the two speakers = 2.00 m

The angle formed between the direction from the microphone to the speaker closest and the directional path between the speakers = 90°

Therefore, by Pythagoras's theorem, the distance from the speaker furthest from the microphone, to the microphone, 'R₂' is given as follows;

R₂ = √(4.50² + 2.00²) = √(24.25) = 4.9244289009 ≈ 4.924

∴ R₂ ≈ 4.9244289 m

R₂ - R₁ = 4.9244289 m - 4.5 m = 0.4244289 m

For constructive interference, R₂ - R₁ =0.4244289 m = n·λ

For n = 1, we have;

R₂ - R₁ =0.4244289 m = n·λ = 1 × λ = λ

λ = 0.4244589 m

f = v/λ = 340 m/sec/(0.4244289 m) ≈ 801.076458 Hz

Therefore the lowest possible fundamental frequency at which the speakers produce constructive interference, f = 801.076458 Hz

7 0
3 years ago
At which temperature does the motion of atoms and molecules stop?
Scorpion4ik [409]

Answer:

0 Kelvin

Explanation:

Atoms in absolute temperature get approximatelly motionless since 0 Kelvin is -273 degrees Celcius. The kinetic energy of atoms/particles in matter has the possible lowest value ( almost zero), so that there is nothing colder than 0 Kelvin.

4 0
3 years ago
Which statement best summarizes the theory of evolution by natural selection?
prisoha [69]

Answer:

c is the one that makes the most sense

Explanation:

8 0
2 years ago
Read 2 more answers
Two airplanes leave an airport at the same time. The velocity of the first airplane is 730 m/h at a heading of 44.3 ◦ . The velo
Goshia [24]

Answer:

So airplane will be 1324.9453 m apart after 2.9 hour

Explanation:

So if we draw the vectors of a 2d graph we see that the difference in angles is  = 83 - 44.3 = 83-44.3=38.7^{\circ}

Distance traveled by first plane = 730×2.9 = 2117 m

And distance traveled by second plane = 590×2.9 = 1711 m

We represent these distances as two sides of the triangle, and the distance between the planes as the side opposing the angle 38.7.

Using the law of cosine, d^2 representing the distance between the planes, we see that:

d^2=2117^2 + 1711^2 -2\times (2117)\times (1711)cos(38.7)=1755480.2482

d = 1324.9453 m

4 0
3 years ago
How many excess electrons must be present on each sphere if the magnitude of the force of repulsion between them is 4.57×10−21 n
hichkok12 [17]

Answer:

891 excess electrons must be present on each sphere

Explanation:

One Charge = q1 = q

Force = F = 4.57*10^-21 N  

Other charge = q2 =q

Distance = r = 20 cm = 0.2 m  

permittivity of free space = eo =8.854×10−12 C^2/ (N.m^2)  

Using Coulomb's law,

F=[1/4pieo]q1q2/r^2

F = [1/4pieo]q^2 / r^2

q^2 =F [4pieo]r^2

q =  r*sq rt F[4pieo]

 q=0.2* sq rt[ 4.57 x 10^-21]*[4*3.1416*8.854*10^-12]

q = 1.42614*10^ -16 C

number of electrons = n = q/e=1.42614*10^ -16 /1.6*10^-19

n =891

 891 excess electrons must be present on each sphere  

5 0
3 years ago
Other questions:
  • Please help on these questions!!!
    6·1 answer
  • A ray passing through optical centre don't deviate ? why​
    13·1 answer
  • Why is the solar cycle said to have a period of 22 years, even though the sunspot cycle is only 11 years long?
    13·1 answer
  • The ___________ of an object consists of its speed and direction.
    10·1 answer
  • Two adjoining plane mirrors are separated by an angle of 100°. Light is incident on the first mirror at an angle of 70°. The lig
    14·2 answers
  • Radio transmissions show observers in Houston that the International Space Station is 323 miles away, the Chi- nese space statio
    13·1 answer
  • A piece of solid copper, at 10oC, is dropped into a graduated cylinder of 100°C water. Which statement BEST describes the change
    10·2 answers
  • Which statement describes the redox reaction involved in photosynthesis?
    10·2 answers
  • What words does convection come from
    13·1 answer
  • Bethany feels as though she cannot enjoy flowers properly, as she has lost her sense of smell. Bethany has _______
    11·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!