The initial velocity of a 4.0-kg box is 11 m/s, due west. After the box slides 4 m horizontally, its speed is 1.5 m/s. Determine the magnitude and the direction of the non-conservative force acting on the box as it slides.

Holly puts a box into the trunk of her car. Later, she drives around an unbanked curve that has a radius of 48 m. The speed of the car on the curve is 16 m/s, but the box remains stationary relative to the floor of the trunk. Determine the minimum coefficient of static friction for the box on the floor of the trunk.  

Water is flowing through a pipeline at the speed of 5 m/s when it encounters a vertical bend in the pipe raising it by 4.0 m. After the rise, the speed of flow reduces to 4 m/s. The cross-sectional area of the pipe does not change. What is the difference in pressure (PB – PA) in the portions of the pipe before and after the rise?  

A rock weighs 30 N in air and 25 N when completely submerged in a fluid with a density of 750 kg/m3.   Determine the density of the rock.

In a well-insulated container, 4.0 kg of water and 3.0 kg of ice are in thermal equilibrium at 0 °C. How much heat is required to bring the system to thermal equilibrium at 45 °C?

What is the pressure difference between the street level and the roof of a 400 m high tower?  (Assume the density of air is 1.29 kg/m3 )

Water enters a pipe of diameter 5 cm with a velocity of 4 m/s. Then the water encounters a constriction and its velocity becomes 16 m/s. What is the diameter of the constricted portion of the pipe?

A system containing an ideal gas at a constant pressure of 1.32 × 105 Pa gains 2120 J of heat.  During the process, the internal energy of the system increases by 2640 J.  What is the change in volume of the gas?

A circular hole in a copper plate is 3.925 cm in diameter at 30.0 °C.  What is the diameter of the hole if the temperature of the plate is raised to 150.0 °C?  The coefficient of linear expansion of copper is 17 × 10–6/C°. 

Sphere 1 has an emissivity of 0.8, its radius is 1 m, and its temperature is 25 °C. Sphere 2 has an emissivity of 0.4, and a radius of 1 m. What should be the temperature of Sphere 2 so it emits radiation at the same power as Sphere 1?