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A cube of wood having an edge dimension of [a] cm and a density of [rho] kg/m3 floats on water. What is the weight of the cube? 1 cm = 10-2 m, 1 cm3 = 10-6 m3. Density of water is 1000 kg/m3. The acceleration due to gravity is g = 9.8 m/s2. Express your answer in N (newtons).

A 0.12-m-radius grinding wheel takes 6.5 s to speed up from 2.0 rad/s to 11.0 rad/s. What is the wheel’s average angular acceleration?

A cube of wood having an edge dimension of [a] cm and a density of [rho] kg/m3 floats on water. What is the distance from the horizontal top surface of the cube to the water level? 1 cm = 10-2 m, 1 cm3 = 10-6 m3. Water’s density is 1000 kg/m3, and its acceleration due to gravity is g = 9.8 m/s2. Express your answer in cm.

An ideal diatomic gas expands adiabatically from [V1] m3 to [V2] m3. If the initial pressure and temperature are [p1]×105 Pa and [T1] K, respectively, find the work done on the gas. Express your answer in kJ. 1 kJ = 103 J. The universal gas constant is R = 8.314 J/mol.K. The ratio of molar specific heat at constant pressure to that at constant volume (adiabatic index of the gas) for the ideal diatomic gas is 

Two forces act on a 8.50-kg object. One of the forces is 14.0 N. If the object accelerates at 3.50 m/s2, what is the greatest possible magnitude of the other force?

n=[n] moles of an argon gas are at a temperature of  [T] K. Calculate the kinetic energy per molecule. The Boltzmann’s constant is kB = 1.38 ×10-23 J/K. The argon gas consists of monatomic molecules. Express your answer in zJ (zepto-joule). 1 zJ = 10-21 J.

n=[n] moles of an argon gas are at a temperature of  [T] K. Calculate the root-mean-square (rms) speed of an atom in the gas. The Boltzmann’s constant is kB = 1.38 ×10-23 J/K. The universal gas constant is R = 8.314 J/(mol.K). The argon’s molar mass is M = 39.95 g/mol = 39.95 ×10-3 kg/mol. Express your answer in m/s.

A solar heated house loses about 5.2 × 107 cal through its outer surfaces on a typical 24-h winter day. What mass of storage rock is needed to provide this amount of heat if it is brought up to initial temperature of 58°C by the solar collectors and the house is maintained at 20°C? (Specific heat of rock is 0.21 cal/g⋅°C.)

A string with mass per unit length μ1 is under tension T1. A wave traveling along this string has a speed v1. A wave traveling along a second string has speed v2. If v2 = 4v1, what could be the tension, T2, and mass per unit length, μ2, of the second string?

Suppose [Q]×105 J of energy are transferred to [m] kg of ice at 0 oC. The heat of fusion of water is Lf = 3.33 × 105 J/kg. The specific heat of water is c = 4186 J/(kg.K). Determine the final temperature of the liquid water in Celsius.