Answer:

Explanation:
From the Question we are told that:
Mass 
Coefficient of kinetic friction 
Generally the equation for Frictional force is mathematically given by



Generally the Newton's equation for Acceleration due to Friction force is mathematically given by



Therefore



Answer:
796.18 Hz
Explanation:
Applying,
Maximum velocity = Amplitude×Angular velocity
Therefore,
V' = A(2πf)............... Equation 1
Where V' = maximum velocity of the eardrum, A = Amplitude of vibration of the eardrum, f = frequency of the eardrum vibration, π = pie
make f the subject of the equation
f = V'/2πA................ Equation 2
From the question,
Given: V' = 3.6×10⁻³ m/s, A' = 7.2×10⁻⁷ m,
Constant: 3.14.
Substitute these values into equation 2
f = 3.6×10⁻³/( 7.2×10⁻⁷×2×3.14)
f = 796.18 Hz
Answer:
Option A. 180000 Kgm/s.
Explanation:
From the question given above, the following data were obtained:
For Train Car A:
Mass of train car A = 45000 Kg
Velocity of train car A = 4 m/s
Momentum of train car A =?
For Train Car B:
Mass of train car B = 45000 Kg
Velocity of train car B = 0 m/s
Momentum is simply defined as the product of mass and velocity. Mathematically, it can be expressed as:
Momentum = mass × velocity
With the above formula, the momentum of train car A before collision can be obtained as follow:
Mass of train car A = 45000 Kg
Velocity of train car A = 4 m/s
Momentum of train car A =?
Momentum = mass × velocity
Momentum = 45000 × 4
Momentum of train car A = 180000 Kgm/s