Explanation:
The net force along the horizontal direction is

where f is the frictional force. We can find the frictional force by looking at the vertical forces acting on the couch:

From the definition of frictional force,


Therefore, the net force on the couch is

Answer:
D
Explanation:
correct me if I'm wrong on your answer and it's the right answer from my son
Answer:
1,8066 x 1024 atoms
Explanation:
1 mole of chromium contains 6,022 x 1023 atoms
so
3 moles of chromium contains 3 times as many atoms
3 x 6,022 x 1023 = 1,8 066 x 1024
No temperature change occurs from heat transfer if ice melts and becomes liquid water (i.e., during a phase change). For example, consider water dripping from icicles melting on a roof warmed by the Sun. Conversely, water freezes in an ice tray cooled by lower-temperature surroundings.
Hope this helped you