Check the attached file for the answer.
Answer:
<u>B. the stars of spectral type A and F are considered reasonably to have habitable planets but much less likely to have planets with complex plant - or animal - like life.</u>
Explanation:
The appropriate spectral range for habitable stars is considered to be "late F" or "G", to "mid-K" or even late "A". <em>This corresponds to temperatures of a little more than 7,000 K down to a little less than 4,000 K</em> (6,700 °C to 3,700 °C); the Sun, a G2 star at 5,777 K, is well within these bounds. "Middle-class" stars (late A, late F, G , mid K )of this sort have a number of characteristics considered important to planetary habitability:
• They live at least a few billion years, allowing life a chance to evolve. <em>More luminous main-sequence stars of the "O", "B", and "A" classes usually live less than a billion years and in exceptional cases less than 10 million.</em>
• They emit enough high-frequency ultraviolet radiation to trigger important atmospheric dynamics such as ozone formation, but not so much that ionisation destroys incipient life.
• They emit sufficient radiation at wavelengths conducive to photosynthesis.
• Liquid water may exist on the surface of planets orbiting them at a distance that does not induce tidal locking.
<u><em>Thus , the stars of spectral type A and F are considered reasonably to have habitable planets but much less likely to have planets with complex plant - or animak - like life.</em></u>
Answer:
The percentage power lost in the transmission line if the voltage not stepped up is 50%.
Explanation:
Given that,
Current = 60 A
Voltage = 120 V
Resistance = 1.0 ohm
We need to calculate the power
Using formula of power
Where,I =current
V = voltage
Put the value into the formula
We need to calculate the percentage power lost in the transmission line
If the voltage is not stepped up
Then, the power loss
Put the value into the formula
The percentage power loss P''
Hence, The percentage power lost in the transmission line if the voltage not stepped up is 50%.
Answer:
Final velocity (v) = 36 m/s
Distance traveled (s) = 2,160 m
Explanation:
Given:
Initial velocity (u) = 0
Acceleration (a) = 0.3 m/s
Time travel (t) = 2 minutes = 120 seconds
Find:
Final velocity (v) = ?
Distance traveled (s) = ?
Computation:
v = u + at
v = 0 + 0.3(120)
v = 0.3(120)
v = 36 m/s
Final velocity (v) = 36 m/s
Distance traveled (s) = ut + (1/2)at²
Distance traveled (s) = (0.5)(0.3 × 120 × 120)
Distance traveled (s) = 2,160 m
