Explanation:
(a) Displacement of an object is the shortest path covered by it.
In this problem, a student is biking to school. She travels 0.7 km north, then realizes something has fallen out of her bag. She travels 0.3 km south to retrieve her item. She then travels 0.4 mi north to arrive at school.
0.4 miles = 0.64 km
displacement = 0.7-0.3+0.64 = 1.04 km
(b) Average velocity = total displacement/total time
t = 15 min = 0.25 hour
Hence, this is the required solution.
Answer:
346 * 10⁶ m
Explanation:
The force of gravity of the earth that will cancel the the force of gravity exerted by the moon will be equal to each other
Let be the force of gravity exerted by the earth
and let be the force of gravity exerted by the moon
According to Newton's law of universal gravitation, the force of attraction between two different masses, m₁ and m₂ separated by a distance, d, is given by:
Mass of the earth,
Mass of the moon,
Mass of the satellite,
...............................(1)
The earth and the moon are separated by a distance, 3.844 * 10⁸ m
............................(2)
Equating equations (1) and (2)
Factorising out
Solving for d in the quadratic equation above:
d = 346 * 10⁶ m