How much heat (in kcal) must be removed to make ice at -10°C from 2 kg of water at 20°C? (The specific heat of ice is 0.50 cal/g×°C.)
a. 190
b. 200
c. 240
d. 210
e. 50
D
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Mass on a Spring: A 3.42-kg stone hanging vertically from an ideal spring on the earth undergoes simple harmonic motion at a place where g = 9.80 m/s2. If the force constant (spring constant) of the spring is 12 N/m, find the period of oscillation of this setup on a planet where g = 1.60 m/s2.
A. 3.35 s B. 2.51 s C. 4.35 s D. 5.70 s
Total Internal Reflection: A thick slab of plastic lies at the bottom of a tank filled with water having an index of refraction of 1.33. A narrow laser beam is shone directly downward through the water on the plastic. You then gradually rotate the laser, thereby increasing the angle with respect to the normal that it strikes the plastic. You carefully note that at the instant the beam makes an angle of 66.5° with the normal in the water, no light enters the plastic, but it did enter for angles smaller than that. What is the speed of light in the plastic slab? (c = 3.00 × 108 m/s)
Fill in the blank(s) with the appropriate word(s).
The refraction of light in a diamond is greater for
A) long-wavelength light. B) short-wavelength light. C) both refract the same
If a hydrogen atom, originally in its ground state of energy –13.6 eV, absorbs a photon of energy 15.9 eV, what is the resulting kinetic energy of the electron if the proton has negligible kinetic energy?
a. 13.6 eV b. –2.30 eV c. 2.30 eV d. 15.9 eV e. Such a photon cannot be absorbed in this case.