1N=1kg•m/s^2 so the answer is 3N
Answer:
Increasing the tension on a string increases the speed of a wave, which increases the frequency (for a given length). Pressing the finger at different places changes the length of string, which changes the wavelength of standing wave, affecting the frequency.
Explanation:
Answer: 11 km/h at 339° compass
Explanation:
A sees B moving south at 0 km/h
A is moving north at 12cos30 = 10.392 km/h
Therefore B must be moving north at 10.392 k/h
A is moving east at 12sin30 = 6 km/h
B appears to be moving west at 10 km/h
Therefore B must be moving west at 10 - 6 = 4 km/h
B is moving v = √(4² + 10.392²) = 11.135... 11 km/h
θ = arctan( -4 / 10.392) = -21.05 = 339°
