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
OLga [1]
3 years ago
13

Which of the following methods has led to the earliest discoveries of massive planets orbiting near their parent stars a. detect

ing a planet ejected from a binary star system b. detecting the starlight reflected off the planet c. detecting the gravitational effect of an orbiting planet (The Wobble"") by looking for the Doppler shifts in the star's spectrum d. detecting the infrared light emitted by the planet
Physics
1 answer:
Mrac [35]3 years ago
3 0

Answer:

c. detecting the gravitational effect of an orbiting planet (The Wobble"") by looking for the Doppler shifts in the star's spectrum

Explanation:

In a solar system the mass of the star and planets affect each other's orbital  movements. The center of gravity of a star and a planet is inside the star. This causes the star to be closer and farther from the Earth at different times. Due to this wobble the star appears to be red shifted when it is farther and blue shifted when it is closer.

When the mass of the planet is high, like a hot Jupiter it causes more wobble i.e., change in radial velocity. This makes it easier to detect the planet. The earliest hot Jupiter found by this method is the planet 51 Pegasi b.

You might be interested in
The magnitudes of two forces are measured to be 120 ± 5 N and 60 ± 3 N. Find the sum and diff erence of the two magnitudes, givi
Pani-rosa [81]

Answer:

62N

Explanation:

4 0
3 years ago
A balloon contains helium with a mass of 0.00296 g. What is the volume of helium in the balloon? (Note: Helium’s density is 0.00
Over [174]

Answer:

178 cm3

Explanation:

From definition of density, it is mass per unit volume of an object, expressed as density=mass/volume and making volume the subject of the above formula we have volume= mass/density and substituting 0.00296 g for mass and 0.00001663 g/cm3 for density then we have

Volume=0.00296/0.00001663

Volume is approximately 178 cm3

7 0
3 years ago
A pelican flying along a horizontal path drops a fish from a height of 4.7 m. The fish travels 9.3 m horizontally before it hits
slavikrds [6]

Answer:

(A) 9.5 m/s

(B) 5.225 m

Explanation:

vertical height (h) = 4.7 m

horizontal distance (d) = 9.3 m

acceleration due to gravity (g) = 9.8 m/s^{2}

initial speed of the fish (u) = 0 m/s

(A) what is the pelicans initial speed ?

  • lets first calculate the time it took the fish to fall

s = ut + (\frac{1}{2}) at^{2}

since u = 0

s =  (\frac{1}{2}) at^{2}

t = \sqrt{\frac{2s}{a} }

where a = acceleration due to gravity and s = vertical height

t = \sqrt{\frac{2 x 4.7 }{9.8} } = 0.98 s

  • pelicans initial speed = speed of the fish

speed of the fish = distance / time = 9.3 / 0.98 = 9.5 m/s

initial speed of the pelican = 9.5 m/s

(B) If the pelican was traveling at the same speed but was only 1.5 m above the water, how far would the fish travel horizontally before hitting the water below?

vertical height = 1.5 m

pelican's speed = 9.5 m/s

  • lets also calculate the time it will take the fish to fall

s = ut + (\frac{1}{2}) at^{2}

since u = 0

s =  (\frac{1}{2}) at^{2}

t = \sqrt{\frac{2s}{a} }

where a = acceleration due to gravity and s = vertical height

t = \sqrt{\frac{2 x 1.5 }{9.8} } = 0.55 s

 

distance traveled by the fish = speed x time = 9.5 x 0.55 = 5.225 m

8 0
3 years ago
A bat can detect small objects such as an insect whose size is approximately equal to the wavelength of the sound the bat makes.
zaharov [31]

Given that,

Frequency emitted by the bat, f = 47.6 kHz

The speed off sound in air, v = 413 m/s

We need to find the wavelength detected by the bat. The speed of a wave is given by formula as follows :

v=f\lambda\\\\\lambda=\dfrac{v}{f}\\\\\lambda=\dfrac{413}{47.6\times 10^3}\\\\\lambda=0.00867\ m

or

\lambda=8.67\ mm

So, the bat can detect small objects such as an insect whose size is approximately equal to the wavelength of the sound the bat makes i.e. 8.67 mm.

3 0
3 years ago
7. An astronaut weighs 900N on earth. On the moon, he weighs 150N. Calculate the
noname [10]

Answer:

Moons’ gravitational strength = weight of astronaut on the moon / mass of astronaut.

= 150 / 90 = 1.67 Nkg-1

Explanation:

7 0
3 years ago
Other questions:
  • What factors affect the speed of a wave? Check all that apply.
    8·2 answers
  • In the early 19th century Christian Doppler, an Austrian physicist, proposed a theory regarding the properties of a moving sourc
    8·1 answer
  • A 42 N net force is applied to a box which slides horizontally across a floor for 9.0
    9·1 answer
  • Given two vectors A⃗ = 4.20 i^+ 7.00 j^ and B⃗ = 5.70 i^− 2.60 j^ , find the scalar product of the two vectors A⃗ and B⃗ .
    5·1 answer
  • A. Consider a charge Q fixed in place at the origin that creates an electric field in the surrounding region. We call a charge w
    9·1 answer
  • A person who is heavier than the standard for the person’s height is _____
    15·2 answers
  • Can someone plz check if what I typed is good :)
    12·1 answer
  • Suppose that the separation between two speakers A and B is 4.80 m and the speakers are vibrating in-phase. They are playing ide
    6·1 answer
  • Match the description with the type of front
    9·1 answer
  • A fighter plane is descending at 30 m/s. The pilot ejects, and the ejector seat accelerates him upwards at 120 m/s2 for 2 second
    5·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!