The object that a satellite revolves around is the <em>central body</em> of the system. <em>(C)</em>
For example:
-- The central body of the solar system is the Sun.
-- The central body for TV satellites, GPS satellites, weather satellites, and the International Space Station is the Earth.
-- The central body for Phobos and Deimos is Mars.
This should be a pretty easy question to answer by elimination, when you notice that "Orbit", "Period", and "Rotation" are not "Bodies".
Explanation:
(c) I assume we're looking for mA.
Sum of forces on B in the -y direction:
∑F = ma
mBg − T = mBa
Sum of forces on A in the +x direction:
∑F = ma
T = mAa
Substitute:
mBg − mAa = mBa
mBg − mBa = mAa
mA = mB (g − a) / a
Plug in values:
mA = (5 kg) (10 m/s² − 0.01 (10 m/s²)) / (0.01 (10 m/s²))
mA = 495 kg
The answer key seems to have a mistake. It's possible they meant mB = 1 kg, or they changed mB to 5 kg but forgot to change the answer.
Answers:
B.) 
C.) 
Explanation:
The image attached shows the way the force 
is acting on the block. Now, if we draw a free body diagram of the situation and write the equations for the Net Force in X and Y, we will have the following:
Net Force in X:
(1)
Where:
is the Normal force
is the magnitude of the force exerted on the block
is the angle
Net Force in Y:
(2)
Where:
is the Friction force (it is expresed with the 
sign because this force may be up or down, we cannot know because the block is at rest)
is the gravity force
Rewrittin (1):
(3) This is according to option B
Rewritting (2):
(3) This is according to option C
I think the answer is c but I’m not sure
Answer:
They are conductors/conductive. Materials that can transfer thermal energy well are conductive.
Explanation:
