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
Aloiza [94]
3 years ago
12

in the history of astronomy, which of the following is true? a. galileo galilei was a student of tycho brahe. b. johannes kepler

built one of the first observatories. c. ptolemy argued that earth was the center of the universe. d. isaac newton was criticized for his work on the geocentric model.
Physics
1 answer:
bija089 [108]3 years ago
7 0
C. Ptolemy argued that earth was the center of the universe
You might be interested in
A train travels 1000 m south for 100 s. What is the
Alexandra [31]
C. 10 m/s
You divide 1000 m by 100 s.
1000/100 to find the velocity
5 0
3 years ago
What is the minimum mass needed for a star to be on the main sequence? What happens to stars that do not meet the minimum mass?
Mariana [72]
Main sequence stars are characterised by the source of their energy.They are all undergoing fusion of hydrogen into helium within their cores. The mass of the star is the main element for such process or phenomenon to take place for it is a determinant of both the rate at which they perform the said activity and the amount of fuel available. 

To answer the question, the lower mass limit for a main sequence star is about 0.08. If the mass of a main sequence star is lower than the above-mentioned value, there would be a deficit or insufficiency of gravitational force to generate a standard temperature for hydrogen core fusion to take place and the underdeveloped star would form into a brown dwarf instead.
6 0
3 years ago
A very long train is rolling at 4 m/s along a straight track. An observer is standing on the ground very dangerously close to th
hichkok12 [17]

Answer:

A. \vec{r}=(6\frac{m}{s})t\ \ \hat{i}

B.  t = 50 s

Explanation:

A. The vectorial equation of the person who is getting closer to the other person is:

\vec{r}=\vec{v}t

r: position vector

v: speed vector = 6m/s i  (if you consider the motion as a horizontal motion)

Then, you replace and obtain:

\vec{r}=(6\frac{m}{s})t\ \ \hat{i}

B. The time is:

t=\frac{d}{v}

d: distance to the observer = 300m

v: speed of the person on the car = 6.00 m/s

t=\frac{300m}{6m/s}=50s

4 0
3 years ago
Which of the following statements about electromagnetic radiation are TRUE? a. Wavelength and frequency are inversely proportion
Kobotan [32]

Answer: A) Wavelength and frequency are inversely proportional.

Explanation:

From the wave equation;

Velocity= frequency × wavelength

If the above equation is rearranged making the frequency the subject of formula, it would give;

Frequency= velocity/ wavelength.

From the above equation we see that frequency is inversely proportional to the wavelength. This means that for every increase in wavelength there would be a decrease in frequency, and for every increase in frequency there is a reduction in wavelength.

7 0
3 years ago
1. A car is slowing down at a constant rate from 40 m/s to come to a stop. The acceleration is - 5 m/s2. How
Oxana [17]

Answer:

           

Explanation:

5 0
3 years ago
Other questions:
  • A spring with an 8-kg mass is kept stretched 0.4 m beyond its natural length by a force of 32 N. The spring starts at its equili
    12·2 answers
  • Choose the most acidic substance in the group.
    8·2 answers
  • The ocean’s surface temperatures vary with time of year and a. latitude. c. seasons. b. longitude. d. moon phases.
    15·2 answers
  • A detailed explanation of static and dynamic friction . plsssss​
    14·1 answer
  • An Object with a mass of 40kg is moving at a velocity of 10 m/s. Determine its kinetic energy
    8·1 answer
  • The foundation of psychology is?<br> Case Studies<br> O Experiments<br> O Research<br> O Analysis
    13·1 answer
  • Need Help Please and Thank You). Question 1: Explain how longitudinal waves and transverse waves are similar to each other and d
    5·1 answer
  • HELPP!!!! URGENT!!!!
    11·1 answer
  • Ginny is snowboarding down a ski slope. Her total mass (including the snowboard) is 68.5 kg. When she reaches the bottom of the
    7·2 answers
  • How does self efficacy relate to sports performance?
    12·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!