Answer:
Explanation:
Photon is also a particle . Hence when two particles like electron and positron annihilate to get completely changed to photons , a minimum of two photons of equal and opposite momentum and energy are produced flying in opposite direction to conserve momentum and energy . Each photon will have same energy equal to 511 keV . It is so to conserve momentum and energy. Initially total momentum was zero so finally too total momentum should be zero.
Here we have perfectly inelastic collision. Perfectly inelastic collision is type of collision during which two objects collide, stay connected and momentum is conserved. Formula used for conservation of momentum is:

In case of perfectly inelastic collision v'1 and v'2 are same.
We are given information:
m₁=0.5kg
m₂=0.8kg
v₁=3m/s
v₂=2m/s
v'₁=v'₂=x
0.5*3 + 0.8*2 = 0.5*x + 0.8*x
1.5 + 1.6 = 1.3x
3.1 = 1.3x
x = 2.4 m/s
Answer: Option (b) is the correct answer.
Explanation:
A gamma particle is basically a photon of electromagnetic radiation with a short wavelength.
Symbol of a gamma particle is
. Hence, charge on a gamma particle is also 0.
For example, 
So, when a nucleus decays by gamma decay to a daughter nucleus then there will occur no change in the number of protons and neutrons of the parent atom but there will be loss of energy as a nuclear reaction has occurred.
Thus, we can conclude that the statement daughter nucleus has the same number of nucleons as the original nucleus., is correct about if a nucleus decays by gamma decay to a daughter nucleus.
Answer:
98.13m
Explanation:
Complete question
Daniel is 50.0 meters away from a building. Tip of the building makes an angle of 63.0° with the horizontal. What is the height of the building
CHECK THE ATTACHMENT
From the figure, using trigonometry
Tan(θ ) = opposite/adjacent
Where Angle (θ )= 63°
Opposite= X = height of the building
Adjacent= 50 m
Then substitute the values we have
Tan(63)= X/50
1.9626= X/50
X= 1.9626 × 50
X= 98.13m
Hence, the height of the building is 98.13m
Answer:
P = 79993.43245
Explanation:
Được -
Vị trí tâm ống dẫn dưới đường thuỷ ngân h1 = 820 mm
Chênh lệch chiều cao của cột thủy ngân h2 = 880mm
Tỷ trọng của thủy ngân = 13,5951 g / cm3
P = mật độ * gia tốc do trọng lực a * h
Thay thế các giá trị đã cho, chúng ta nhận được -
P = 13,5951 g / cm3 * 980,665 cm / s2 * (88-82) cm
P = 79993.43245