<span>Well, It is the aphelion point, When the Earth is farthest away from the Sun, when the Northern Hemisphere is warm. the Earth is closest to the Sun, or at the perihelion, 2 weeks after the June Solstice, when the Northern Hemisphere is enjoying warm summer months. Well this kind of weather is very nice.</span>
Answer:
a. The object will attract the glass rod.
b. The object will repel the glass rod.
Explanation:
a. When you rub a plastic rod with wool, it becomes negatively charged. This is because the wool material loses some of its electrons to the plastic rod. The wool becomes positively charged while the plastic rod becomes negatively charged.
Hence, for an object to repel the negatively charged plastic rod, it must also be negatively charged. This is because objects with like charges repel one another.
On the other hand, when you rub a glass rod with a silk material, it becomes positively charged. This is because the glass rod loses its electrons to the silk material. The silk material then becomes negatively charged, while the glass rod becomes positively charged.
Therefore, the negatively charged object will attract the already positively charged glass rod.
b. For an object to attract a negatively charged plastic rod, then it must be positively charged, since unlike charges attract.
So, a positively charged object will repel the negatively charged glass rod.
Answer:

Explanation:
What problem says can be written mathematically as:

Where:

The problem itself it's really simple, we only need to replace the data provided in the previous equation, but first, let's convert the units of the velocity from cm/s to m/s because we have to work with the same units and working in meters is the most apropiate action, because is the base unit of length in the International System of Units:

Now, we can replace the data in the equation and find the time it will take the bird to travel 3.7 m:

Solving for t, multiplying by t both sides, and dividing by 0.52 both sides:

Answer with Explanation:
Let rest mass
at point P at distance x from center of the planet, along a line connecting the centers of planet and the moon.
Mass of moon=m
Distance between the center of moon and center of planet=D
Mass of planet=M
We are given that net force on an object will be zero
a.We have to derive an expression for x in terms of m, M and D.
We know that gravitational force=
Distance of P from moon=D-x
=Force applied on rest mass due to m
=Force on rest mass due to mas M
because net force is equal to 0.





Let 
Then, 




b.We have to find the ratio R of the mass of the mass of the planet to the mass of the moon when x=
Net force is zero




Hence, the ratio R of the mass of the planet to the mass of the moon=4:1