Air resistance doesn't appear in the formula for gravitational force, because it doesn't affect it. Mass does because it does.
In almost every case in nature, adding heat to a liquid
causes the density of the liquid to decrease. That is,
when the liquid gets warmer, it expands and occupies
more space.
The one big exception to this rule is water !
Starting with a block of ice at zero°C (32°F), as the ice melts,
becomes water at zero°C, and all the way to 4°C (about 39°F),
its density increases all the way. That is, it shrinks and occupies
less volume as it goes from ice at zero°C to water at 4°C.
This sounds like an interesting but insignificant quirk ... until
you realize that if water didn't do this, then life on Earth would
be impossible !
Answer:

Explanation:
Starting from the equation:

First of all, let's multiply by t on both sides:

And then, let's divide by v on both sides:

So, finally

Answer:

Explanation:
Given:
- time taken by the sun to complete one revolution,

- radial distance of the sunspot,

<u>Therefore, angular speed of rotation of sun:</u>

<u>Now the tangential velocity of the sunspot can be given by:</u>



Answer:
the smallest separation between two objects is 0.8067 m
Explanation:
Given the data in the question;
Altitude h = 5.75 km = 5750 m
Diameter D = 4.0 mm = 0.004 m
λ = 460 nm = 4.6 × 10⁻⁷ m
Now, Using Rayleigh criterion for Airy disks resolution.
we know that, Minimum angular separation for resolving two points is;
θ = 1.22λ / D
so we substitute
θ = (1.22 × 4.6 × 10⁻⁷) / 0.004
θ = 5.612 × 10⁻⁷ / 0.004
θ = 1.403 × 10⁻⁴ rad
so minimum separation
= θh
so we substitute
= (1.403 × 10⁻⁴) × 5750 m
= 0.8067 m
Therefore, the smallest separation between two objects is 0.8067 m