Answer:
43.2 N
Explanation:
= Wavelength = 0.75 m
f = Frequency = 40 Hz
m = Mass of string = 0.12 kg
L = Length of string = 2.5 m
= Linear density = 
Velocity of wave is given by

The tension in string is given by

The tension in the string is 43.2 N
Explanation:
Because it's a power to turn the wheels of industry
The answer to your question is A
Answer:
3.036×10⁻¹⁰ N
Explanation:
From newton's law of universal gravitation,
F = Gm1m2/r² .............................. Equation 1
Where F = Gravitational force between the balls, m1 = mass of the first ball, m2 = mass of the second ball, r = distance between their centers.
G = gravitational constant
Given: m1 = 7.9 kg, m2 = 6.1 kg, r = 2.0 m, G = 6.67×10⁻¹¹ Nm²/C²
Substituting into equation 1
F = 6.67×10⁻¹¹×7.9×6.1/2²
F = 321.427×10⁻¹¹/4
F = 30.36×10⁻¹¹
F = 3.036×10⁻¹⁰ N
Hence the force between the balls = 3.036×10⁻¹⁰ N
D. Mineral and fossil matches from tests done on different continents.