Answer:
Explanation:
The density changes means that the length in the direction of the motion is changed.
Therefore,
Given :
Side, b = h = 0.13 m
Mass, m = 3.3 kg
Density = 8100 
So,
l = 0.024 m
Then for relativistic length contraction,
Therefore, the speed of the observer relative to the cube is 0.9833 c (in the units of c).
<h3><u>Answer</u> :</h3>
Initial velocity = zero (i.e., free fall)
Final velocity = 30m/s
Acceleration due to gravity = 10m/s²
For a body falling freely under the action of gravity, g is taken positive
◈ <u>First equation of kinenatics</u> :
⇒ v = u + gt
⇒ 30 = 0 + 10t
⇒ t = 30/10
⇒ <u>t = 3s</u>
Hence, object will attain a speed of 30m/s after 3s.
300 000 000 m/s in km/s
1000 m = 1km
300 000 000 m/s = 3 * 10⁸ m/s = 3 * 10⁵ *10³ m/s
= 3 * 10⁵ *10³ m/s
= 3 * 10⁵ km/s
Speed = 3 * 10⁵ km/s
When the core runs out of hydrogen to fuse, then it starts fusing the helium. This happens because a star cannot create more hydrogen.
