If the ladder is vertical, then the work done in ascending equals his increase in potential energy.
For a man of mass (m) climbing height (h), the PE is (mgh), where g is the acceleration due to gravity.
If he does this in time t, his average power (rate of working) is:
mgh / t
= 80 * 9.81 * 6 / 12
= 392.4 W.
If the ladder is not vertical but inclined at an angle the horizontal, the power is mgh sin(a) / t.
Answer:
(I). The store energy is 0.432 J.
(II). The energy density is 687.54 J/m³.
Explanation:
Given that,
Voltage = 12.0 V
Capacitor = 6.00 mf
Radius = 0.1 m
Distance = 10 mm
(I). We need to calculate the energy store
Using formula of store energy
Where, C = capacitor
V = voltage
Put the value into the formula
(II). We need to calculate the energy density
Using formula of energy density
Where, r = radius
d = distance
Put the value into the formula
Hence, (I). The store energy is 0.432 J.
(II). The energy density is 687.54 J/m³.
Answer:
C. loses heat, temperature decreases
Explanation:
When gas condenses, energy decreases, therefore it would lose heat and the temperature would decrease.
The last equation gives you the tension in the string on the right:
Answer:
<u>36 m</u>
Explanation:
We can consider this to be an AP.
Then,
<u>Subtract a₇ from a₉.</u>
- a + 8d - a + 6d = 24 - 20
- 2d = 4
- d = 2
<u>Finding a₁₅</u>
- a₁₅ = a + 14d
- a₁₅ = 8 + 14(2)
- a₁₅ = 8 + 28
- a₁₅ = <u>36 m</u>