Answer:
D
Explanation:
According to newton's 2nd law rate of change of momentum is directly proportional to the force applied on the body. Since, net Force is zero this means momentum did not change or momentum of the body remained constant.
Hence, the system have constant value of momentum. Therefore, option D is correct.
Answer:
The mass of the rule is 56.41 g
Explanation:
Given;
mass of the object suspended at zero mark, m₁ = 200 g
pivot of the uniform meter rule = 22 cm
Total length of meter rule = 100 cm
0 22cm 100cm
-------------------------Δ------------------------------------
↓ ↓
200g m₂
Apply principle of moment
(200 g)(22 cm - 0) = m₂(100 cm - 22 cm)
(200 g)(22 cm) = m₂(78 cm)
m₂ = (200 g)(22 cm) / (78 cm)
m₂ = 56.41 g
Therefore, the mass of the rule is 56.41 g
Answer:

Explanation:
From the question we are told that
Weight of fireman 
Pole distance 
Final speed is 
Generally the equation for velocity is mathematically represented as

Therefore Acceleration a
Generally the equation for Frictional force
is mathematically given as



Therefore

Answer:
Sound waves. Anything that vibrates is producing sound; soundis simply a longitudinal wave passing through a medium via the vibration of particles in themedium. Consider a sound wavetraveling in air