Answer:
m = 0.0125 kg
Explanation:
Let us apply the formula for the speed of a wave on a string that is under tension:

where F = tension force
μ = mass per unit length
Mass per unit length is given as:
μ = m / l
where m = mass of the string
l = length of the string
This implies that:

Let us make mass, m, the subject of the formula:

From the question:
F = 20 N
l = 4.50 m
v = 85 m/s
Therefore:

No the only thing that affects it is how it is built
Answer:
The answer is given below
Explanation:
u is the initial velocity, v is the final velocity. Given that:

a)
The final velocity of cart 1 after collision is given as:

The final velocity of cart 2 after collision is given as:

b) Using the law of conservation of energy:

Answer:
False
Explanation:
The steel ball and the wooden ball do not have the same force acting on them because their masses are different. But, they have the same acceleration which is the acceleration due to gravity g = 9.8 m/s².
Using the equation of motion under freefall, s = ut +1/2gt². Since u = 0,
s = 1/2gt² ⇒ t = √(2s/g)
Since. s = height is the same for both objects, they land at the same time neglecting air resistance.