Answer:
Explanation:
point a represents time 0 and position coordinate 30
point b represents time 10 s , and position coordinate 50 m .
time elapsed = 10 - 0 = 10 s .
displacement = 50 m - 30 m
= 20 m
average velocity = displacement / time elapsed
= 20 / 10
= 2 m /s .
A) 8.11 m/s
For a satellite orbiting around an asteroid, the centripetal force is provided by the gravitational attraction between the satellite and the asteroid:

where
m is the satellite's mass
v is the speed
R is the radius of the asteroide
h is the altitude of the satellite
G is the gravitational constant
M is the mass of the asteroid
Solving the equation for v, we find

where:




Substituting into the formula,

B) 11.47 m/s
The escape speed of an object from the surface of a planet/asteroid is given by

where:




Substituting into the formula, we find:

Answer:
The elevator must be moving upward.
Explanation:
During the motion of an elevator, the weight of the person deviates from his or her actual weight. This temporary weight during the motion is referred to as "Apparent Weight". So, when the elevator is moving downward, the apparent weight of the person becomes less than his or her actual weight.
On the other hand, for the upward motion of the elevator, the apparent weight of the person becomes more than the actual weight of that person.
Since the apparent weight (645 N) of the student, in this case, is greater than the actual weight (615 N) of the student.
<u>Therefore, the elevator must be moving upward.</u>