Moon eclipse is when the moon interposes between the sun and behind the Earth. The moon passes behind the Earth into its umbra and not viceversa! This is possible when the three of them are ALIGNED (in syzygy). In Romania, there was such eclipse that could be seen at an October night last year.
Answer:
11.1 m/s
Explanation:
120 km = 120 x 1,000 = 120,000 m
3 hours = 3 x 60 x 60 = 3600 x 3 = 10,800 s
speed = 120,000 / 10,800
= 1200/108
= 11.1 m/s
Answer:
Explanation:
The total energy of the satellite when it is still in orbit is given by the formula
where
G is the gravitational constant
m = 525 kg is the mass of the satellite
is the Earth's mass
r is the distance of the satellite from the Earth's center, so it is the sum of the Earth's radius and the altitude of the satellite:
So the initial total energy is
When the satellite hits the ground, it is now on Earth's surface, so
so its gravitational potential energy is
And since it hits the ground with speed
it also has kinetic energy:
So the total energy when the satellite hits the ground is
So the energy transformed into internal energy due to air friction is the difference between the total initial energy and the total final energy of the satellite:
Answer:
The frictional torque is
Explanation:
From the question we are told that
The mass attached to one end the string is
The mass attached to the other end of the string is
The radius of the disk is
At equilibrium the tension on the string due to the first mass is mathematically represented as
substituting values
At equilibrium the tension on the string due to the mass is mathematically represented as
The frictional torque that must be exerted is mathematically represented as
substituting values