Just as Prof. Newton said: "For every action, there is an EQUAL, OPPOSITE reaction.". (See his motion law #3.)
If our person APPLIED a force of 80N pointing to the right, then that's the 'action'. It must follow, as the night follows the day, that the strength of the equal REaction is also 80N, and it points to the left because it's opposite to the action.
Answer:
Length of the string = 0.24 m
Explanation:
The frequency (f) of vibration of stringed instruments is related to the Tension (T) in the spring by the relation
fₙ = (n/2L)√(T/μ)
where n = 1,2,3,4...
For third harmonic frequency, n = 3
L = length of the string = ?
T = tension in the string = 2.3 N
μ = linear density = 4.6 × 10⁻³ kg/m
f = frequency = 140 Hz
L = (n/2f)√(T/μ)
L = (3/(2×140))√(2.3/0.0046) = 0.40 m
She can climb 0.92 m without losing weight.
<u>Explanation</u>:
Gravitational potential energy is the energy consisting of the product of mass, gravity and height.
1 cal = 4184 J
140 cal = 585760 J
Energy = 585760 J, m = 65.0 kg = 65000 g, Efficiency = 20 %
GPE = mgh
where m represents the mass
g represents the gravity,
h represents the height.
585760 = 65000 
9.8 h
h = 0.92 m.
