Answer:
171.5 N
Explanation:
The gravitational force on an object due to the Earth is given by
where
m is the mass of the object
g is the acceleration due to gravity
The acceleration due to gravity at a certain height h above the Earth is given by
where:
G is the gravitational constant
is the Earth's mass
is the Earth's radius
Here,
So the acceleration due to gravity is
We know that the mass of the object is
m = 70 kg
So, the gravitational force on it is
The observable universe<span> is a spherical region of the </span>Universe, <span>comprising all matter that can be observed from Earth at the present time, because light and other signals from these objects have had time to reach Earth since the beginning of the cosmological expansion.
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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.
Answer:
carpet
Explanation:
Diffuse reflection is the reflection of light from a surface such that an incident ray is reflected at many angles rather than at just one angle as in the case of specular reflection.
The structure of carpet's surface is as shown. Thus it shows large amount of diffuse reflection.
It decomposes into CH3COO- and H+ when dissolved in water. The H+ ions react with the water molecules to generate H3O+, making the solution acidic. When NaOH is added to water, it separates into Na+ and OH-. The sodiums have little effect on the solution, but the hydroxyls make it more basic.
