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
Gwar [14]
3 years ago
13

Which years had the least sunspot activity?

Physics
1 answer:
Nostrana [21]3 years ago
3 0

The period between about 1650 and 1700 is when astronomers saw virtually no sunspot activity.
You might be interested in
A musical note has a frequency of 512 Hz. If the wavelength of the note is 0.685 m, what is the speed of the sound of that note?
riadik2000 [5.3K]

Answer:

350.72 m/s

Explanation:

Formula for velocity of wave is;

v = fλ

Where;

v is speed

f is frequency

λ is wavelength

We are given;

f = 512 Hz

λ = 0.685 m

Thus;

v = 512 × 0.685

v = 350.72 m/s

5 0
3 years ago
Assume that the average mass of each of the approximately 1 billion people in China is 55 kg.Assume that they all gather in one
Harman [31]

Answer: 5.9(10)^{-8} m

Explanation:

The equation to calculate the center of mass C_{M} of a particle system is:

C_{M}=\frac{m_{1}r_{1}+m_{1}r_{1}+...+m_{n}r_{n}}{m_{1}+m_{2}+...+m_{n}}

In this case we can arrange for one dimension, assuming the geometric center of the Earth and the ladder are on a line, and assuming original center of mass located at the Earth's geometric center:

C_{M}=\frac{m_{E}(0 m) + m_{p} r_{E-p}}{m_{E}+m_{p}}

Where:

m_{E}=5.9(10)^{24} kg is the mass of the Earth

m_{p}=55(10)^{9} kg is the mass of 1 billion people

r_{E}=6371000 m is the radius of the Earth

r_{E-p}=6371000 m- 2m=6370998 m is the distance between the center of the Earth and the position of the people (2 m above the Earth's surface)

C_{M}=\frac{m_{p}55(10)^{9} kg (6370998 m)}{5.9(10)^{24} kg+55(10)^{9} kg}

C_{M}=5.9(10)^{-8} m This is the displacement of Earth's center of mass from the original center.

8 0
3 years ago
What is the relationship between matter and energy as it changes states of matter (phase changes?)
AlekseyPX

These energy exchanges are not changes in kinetic energy. They are changes in bonding energy between the molecules. If heat is coming into a substance during a phase change, then this energy is used to break the bonds between the molecules of the substance. The example we will use here is ice melting into water.

7 0
3 years ago
1. Which word or phrase best describes entropy?
Mama L [17]
The answer to this question is:

D) Disorder
7 0
3 years ago
Read 2 more answers
A river flows due south at 5 mi/h. A swimmer attempting to cross the river heads due east swimming at 3 mi/h relative to the wat
Dafna11 [192]

Answer:

<u>velocity of swimmer relative to ground = 3 i -5 j</u>

Explanation:

  • To cross a river the swimmer swims relative to river in perpendicular direction.

Velocity of river = -5 j (south)

Velocity of swimmer relative to river = 3 i(north)

So

<h2>Velocity of swimmer relative to ground = Velocity of swimmer relative to river + Velocity of river</h2>

Velocity of swimmer relative to ground = 3 i -5 j

So magnitude of total velocity is \sqrt{3^2+(-5)^2} =\sqrt{9+25} = \sqrt{34}

3 0
3 years ago
Other questions:
  • When two or more elements chemically combine the result is?
    14·1 answer
  • The period of a wave is 10 seconds and it’s wavelength is 2 meters. What is the wave’s speed?
    8·1 answer
  • A stone with a mass of 0.70 kg is attached to one end of a string 0.70 m long. The string will break if its tension exceeds 65.0
    5·1 answer
  • Which state is the smartest state?
    6·2 answers
  • When thermal energy is added to an object what happens to the motion of the particles
    6·2 answers
  • Camouflage is to blend in with what​
    11·1 answer
  • How does the declining biodiversity affect us?
    6·2 answers
  • If you were rolling a toy car down an incline, what would happen if you made the incline steeper? Explain why this happens using
    13·1 answer
  • The rate of change of momentum of a body free falling under gravity is equal to its? A. Velocity B. kinetic energy C. power D. w
    15·2 answers
  • Human centrifuges are used to train military pilots and astronauts in preparation for high-g maneuvers. A trained, fit person we
    8·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!