Problem-Solving Tip: When cutting an FBD through an axial member, assume that the internal force is tension and draw the force arrow directed away from the cut surface. If the computed internal force value turns out to be a positive number, then the assumption of tension is confirmed.
Answer:
Answer: ±0.02 units or 20±0.02 units or 19.98-20.02 units depending on how they prefer its written (typically the first or second one)
Explanation:
says on the sheet. Unless otherwise stated 0.XX = ±0.02 tolerance
(based on image sent in other post)
Answer: (a). E = 3.1656×10³⁴ √k/m
(b). f = 9.246 × 10¹² Hz
(c). Infrared region.
Explanation:
From Quantum Theory,
The energy of a proton is proportional to the frequency, from the equation;
E = hf
where E = energy in joules
h = planck's constant i.e. 6.626*10³⁴ Js
f = frequency
(a). from E = hf = 1 quanta
f = ω/2π
where ω = √k/m
consider 3 quanta of energy is lost;
E = 3hf = 3h/2π × √k/m
E = (3×6.626×10³⁴ / 2π) × √k/m
E = 3.1656×10³⁴ √k/m
(b). given from the question that K = 15 N/m
and mass M = 4 × 10⁻²⁶ kg
To get the frequency of the emitted photon,
Ephoton =hf = 3h/2π × √k/m (h cancels out)
f = 3h/2π × √k/m
f = 3h/2π × (√15 / 4 × 10⁻²⁶ )
f = 9.246 × 10¹² Hz
(c). The region of electromagnetic spectrum, the photon belongs to is the Infrared Spectrum because the frequency ranges from about 3 GHz to 400 THz in the electromagnetic spectrum.
Answer:
The Poisson's Ratio of the bar is 0.247
Explanation:
The Poisson's ratio is got by using the formula
Lateral strain / longitudinal strain
Lateral strain = elongation / original width (since we are given the change in width as a result of compession)
Lateral strain = 0.15mm / 40 mm =0.00375
Please note that strain is a dimensionless quantity, hence it has no unit.
The Longitudinal strain is the ratio of the elongation to the original length in the longitudinal direction.
Longitudinal strain = 4.1 mm / 270 mm = 0.015185
Hence, the Poisson's ratio of the bar is 0.00375/0.015185 = 0.247
The Poisson's Ratio of the bar is 0.247
Please note also that this quantity also does not have a dimension
