Engineering Board Exam Reviewer · Physics · medium
A steel rail 50 m long is heated from 10 °C to 40 °C. How much does it expand? ( = 12 × 10-6 /° C)
- 24.0 mm
- 18.0 mm
- 54.0 mm
- 1.8 mm
Answer
B. 18.0 mm
Solution
L = L0 T = (12 × 10-6)(50)(30) = 0.0180 m = 18.0 mm.
More Physics questions
- A spaceship travels at 0.8c relative to Earth. A clock on the ship measures 10 years. How much time elapses on Earth?
- In the Bohr model of hydrogen (En = -13.6/n2 eV), how much energy is emitted when an electron drops from n = 2 to n = 1?
- What is the decay constant of an isotope with a half-life of 8 days?
- A fossil contains 25% of the carbon-14 found in living organisms. If the half-life of C-14 is 5730 years, how old is the fossil?
- A sample contains 80 g of a radioactive isotope with a half-life of 10 years. How much remains after 30 years?
- A radioactive sample has a half-life of 5 days. What fraction remains after 20 days?
- How much energy is equivalent to 1 g of mass? (c = 3 × 108 m/s)
- What is the de Broglie wavelength of an electron moving at 1 × 106 m/s? (h = 6.626 × 10-34 J· s, me = 9.109 × 10-31 kg)
- Light of wavelength 400 nm falls on a metal with a work function of 2.3 eV. What is the maximum kinetic energy of the ejected…
- What is the energy of a photon with a wavelength of 500 nm? (h = 6.626 × 10-34 J· s, c = 3 × 108 m/s)