Answer:
3. relatively high temperature, about 10,000 K, so that significant numbers of electrons are excited from the ground state, n = 1, to the first excited state, n = 2, but not too many of them have been ejected completely from the atoms
Explanation:
If hydrogen absorption lines are very strong in the visible spectrum of a particular star that means the population of electron in n = 2 is very high so on being exited they absorb radiation in Balmer series and give rise to absorption spectrum. The average temperature required to excite electron in hydrogen atom from n=1 to n = 2 is 10000K .
Answer:
Shear stress, force tending to cause deformation of a material by slippage along a plane or planes parallel to the imposed stress. The resultant shear is of great importance in nature, being intimately related to the downslope movement of earth materials and to earthquakes.
Answer:
Fx = 35.36 N
Fy = 35.36 N
Explanation:
From the question,
The X component of the force is
Fx = Fcos∅.................. Equation 1
Where Fx = X component of the force, F = Force, ∅ = Angle to the horizontal.
Give: F = 50 N, ∅ = 45°
Substitute into equation 1
Fx = 50(cos45°)
Fx = 50(0.7071)
Fx = 35.36 N
Similarly,
For Y component
Fy = Fsin∅
Where F y = Y component
Fy = 50(sin45°)
Fy = 50(0.7071)
Fy = 35.36 N
<u>Answer:</u>
1) Distance traveled by bird = 403 meter
2)Average speed = 1.66 km /hour
3) Zcceleration = 2 
<u>Explanation:</u>
1) Distance traveled = Speed * Time taken = 31 * 13 = 403 meter.
2) Average speed = Total distance covered / Time taken for that distance to cover.
Total distance covered = 2+0.5+2.5 = 5 km
Time taken = 3 hours
Average speed = 5/3 = 1.66 km /hour
3) Acceleration is defined as the rate of change of velocity, so acceleration a = change in velocity/time.
Change in velocity = 14 - 6 = 8 m/s
Time = 4 seconds
So acceleration = 8 / 4 = 2 