Air expands as it warms. Therefore warm air is less dense than cool air. The warm air from the first floor apartments rises to the second floor. People on the second floor require less heating to keep their <span>apartments comfortable.
-Hope this helps </span>
Answer:
g = 1.64m/s²
Explanation:
1.5m in 0.078s
V = 15 / 0.078
= 19.23m/s
Tension = mg
μ = 3.10 × 10⁻⁴
T = V²μ
mg = V²μ
g = V²μ / m
g = ((19.23)²(3.10 × 10⁻⁴)) / (0.070)
g = 1.64m/s²
Answer:
619.8 N
Explanation:
The tension in the string provides the centripetal force that keeps the rock in circular motion, so we can write:

where
T is the tension
m is the mass of the rock
v is the speed
r is the radius of the circular path
At the beginning,
T = 50.4 N
v = 21.1 m/s
r = 2.51 m
So we can use the equation to find the mass of the rock:

Later, the radius of the string is decreased to
r' = 1.22 m
While the speed is increased to
v' = 51.6 m/s
Substituting these new data into the equation, we find the tension at which the string breaks:
