Answer:
4.25 m/s
Explanation:
They walked the first distance at 5.50 m/s, then the same distance at 3 m/s.
Since the distances are equal, the average speed is simply the average of 5.50 and 3.
(5.50 + 3) / 2 = 4.25
Her average speed over the entire trip is 4.25 m/s.
Answer:
If you push horizontally with a small force, static friction establishes an equal and opposite force that keeps the book at rest. As you push harder, the static friction force increases to match the force. Eventually maximum static friction force is exceeded and the book moves.
Explanation:
Answer: Try C
Explanation:
It's the only one that makes since.
The photon can be absorbed and the energy of the photon is exactly equal to the energy-level difference between the ground state and the level d.