Answer:
Speed at which the ball passes the window’s top = 10.89 m/s
Explanation:
Height of window = 3.3 m
Time took to cover window = 0.27 s
Initial velocity, u = 0m/s
We have equation of motion s = ut + 0.5at²
For the top of window (position A)

For the bottom of window (position B)


We also have

Solving

So after 1.11 seconds ball reaches at top of window,
We have equation of motion v = u + at

Speed at which the ball passes the window’s top = 10.89 m/s
Black balls with blue waffles
Answer: Tension = 47.8N, Δx = 11.5×
m.
Tension = 95.6N, Δx = 15.4×
m
Explanation: A speed of wave on a string under a tension force can be calculated as:

is tension force (N)
μ is linear density (kg/m)
Determining velocity:


0.0935 m/s
The displacement a pulse traveled in 1.23ms:


Δx = 11.5×
With tension of 47.8N, a pulse will travel Δx = 11.5×
m.
Doubling Tension:



|v| = 0.1252 m/s
Displacement for same time:


15.4×
With doubled tension, it travels
15.4×
m
Answer: I would choose options C and D
Explanation: