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A pebble rolls off the roof of Science Hall and falls vertically. Just before it reaches the ground, the pebble’s speed is 17 m/s. Neglect air resistance and determine the height of Science Hall

At time t = 0 s, a puck is sliding on a horizontal table with a velocity 3.60 m/s, 35.0° above the +x axis. As the puck slides, a constant acceleration acts on it that has the following components: ax = –0.360 m/s2 and ay = –0.980 m/s2 . What is the velocity of the puck at time t = 1.50 s?

Water enters a pipe of diameter 8 cm with a velocity of 3 m/s. Then the water encounters a constriction and its velocity becomes 12 m/s. What is the diameter of the constricted portion of the pipe?

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.

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°. 

A heat engine is used to lift a 3000-kg load to a height of 4 m at a constant speed. During the lifting process, the engine received 500,000 J of heat from the fuel burned in its interior. What is the efficiency of the engine?

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?  

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?

A rock weighs 20 N in air and 15 N when completely submerged in a fluid with a density of 800 kg/m3.   Determine the density of the rock.