Answer:
8.2N
Explanation:
I took the test and got it right :)
Answer:
(i) The maximum acceleration upward is 2.02 m/s².
(ii) The maximum acceleration downward is 1.39 m/s².
Explanation:
Let a be the maximum acceleration of the elevator.
The mass of the person at ground is 150 lb. We have to convert the mass into kg,
1 lb = 0.453592 kg
150 lb = 68 kg
170 lb = 77 kg
120 lb = 54 kg
(i) The person experience a force due to Earth's gravity in the downwards direction. The magnitude of this force is:
F₁ = mg = 68 x 9.8 = 666.4 N
The weight of the person decreases as the elevator is moving upwards. So, the force experienced by the person in this case due to gravity is:
F₂ = 54 x 9.8 = 529.2 N
Applying Newton's force equation;
(F₁ - F₂) = ma
(666.4 - 529.2) = 68 x a
a = 2.02 m/s²
(ii) The weight of the person increases as the elevator is moving downwards. So, the force experienced by the person in this case due to gravity is:
F₂ = 77 x 9.8 = 754.6 N
Applying Newton's force equation;
(F₁ - F₂) = ma
(666.4 - 754.6) = 68 x a
a = -1.30 m/s²
Answer:
Explanation:
The Carnot cycle is a special case of a thermodynamic cycle that produces an ideal gas and consists of two isothermal processes and two adiabatic processes. This cycle is a theoretical solution given by Sadi Karnot to refine heat engines for their efficient use.
The formula for the coefficient of efficiency is:
η = (Q₁ - Q₂) / Q₁ = (T₁ - T₂) / T₁
Where Q₁ is is the amount of heat of the heater supplied to the working body and Q₂ is the amount of heat that the working body transfers to the refrigerator according to this T₁ is the temperature of the heater T₂ is the temperature of the refrigerator.
This formula provides a theoretical limit for the maximum value of the coefficient of efficiency of heat engines.
God is with you!!!