I believe it's the the third one. :)
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Answer:
18.03 N
Explanation:
From the fiqure below,
Using parallelogram law of vector
R² = 15²+5²-2×5×15cos(180-60)
R² = 225+25-150cos120°
R² = 250-150(-0.5)
R² = 250+75
R² = 325
R = √325
R = 18.03 N
Hence the resultant force of the object is 18.03 N
Answer:
energy is equal to 1000 J
Explanation:
When the jumper is in the tent, he has a given height, this height gives him a gravitational potential energy, which forms his initial mechanical energy of 1000 J. After jumping, this energy is converted into elastic energy of the rope plus a remainder of potential energy gravitational, it does not reach the ground, but as the friction is negligible the total mechanical energy is conserved, therefore its energy is equal to 1000 J
This is a case of energy transformation, but the total value of mechanical energy does not change
The relationship between the number of visible spectral lines are identical for atoms .However they have unique wavelengths.
Option B
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Explanation:</u>
A spectrum is a range of frequencies or a range of wavelengths. The photon energy of the emitted photon is equal to the difference between two states. For every atom there are quite many electron transitions and each has a energy difference.
This difference in wavelength causes spectrum .As each element emission spectrum is unique because each atom has different energy and causes uniqueness in the emission spectrum . Hence, due to the difference in energy it emits different wavelengths.