A copper ball that is 1.5 m in diameter has a temperature of 100C. The environment is at 0C. If the emissivity of copper is 0.15 how much power is radiated by the copper ball?
(A) 6 w
(B) 5,264 W
(C) 500 W
(D) 1,164 W
What is the natural frequency of a body that has a period of oscillation of 2.7 seconds?
(A) 2.7 s (B) 0.75 s (C) 2.33 s (D) 4.65 s
Correct Answer: C
An iron sphere with a mass of 1.5 kg hangs from a 15 cm long spring. If the spring constant is 0.75 N/m what is the period of oscillation when the sphere is pulled down and released?
(A) 3.2 s (B) 8.9 s (C) 4.4 s (D) 12.5 s
Correct Answer: B
What is the thermal efficiency for a Carnot engine that operates between 100F and 400K?
(A) 75% (B) 77.5% (C) 7.8% (D) 22.3%
Correct Answer: D
More PE Exam Questions
- 1Which of the following statements is FALSE when concerning the hot working of metal?
- 2What is the thermal efficiency for a Carnot engine that operates between 100F and 400K?
- 3Which of the following is FALSE with regards to creep I. May involve the sliding of whole grains II At high stresses creep is controlled by the movement of vacancies. III Also known as hot flow IV Creep is a time dependent deformation
- 4Which of the following can not be equal to 1 mol of the substance at standard conditions?
- 5What would the annuity be over a 20 year period that has an interest rate of 10% and a present worth of $500?