Answer:
Kepler's First Law: each planet's orbit about the Sun is an ellipse. The Sun's center is always located at one focus of the orbital ellipse. The Sun is at one focus. The planet follows the ellipse in its orbit, meaning that the planet to Sun distance is constantly changing as the planet goes around its orbit.
Explanation:
Newton's second law:
∑F = ma
277 N − 245 N = (25 kg) a
a = 1.28 m/s²
Electrical energy.................
Answer:

Explanation:
information we have:
mass: 
lenght: 
frequency: 
time: 
and from the information we have we can calculate the angular velocity
. which is defined as


----------------------------
Now, to calculate the torque
We use the formula

where
is the moment of inertia and
is the angular acceleration
moment of inertia of a uniform rod about the end of it:

substituting known values:

for the torque we also need the acceleration
which is defined as:

susbtituting known values:

and finally we substitute
and
into the torque equation
: