2. A railroad diesel engine weighs six times as much as a freight car. If the diesel engine coasts a 7km per hour into a freight car that is intially at rest, how fast do the tow coast after they couple together?
3. A car moving at 20km.h skids 10m with locked brakes. How far will the car skid with locked brakes at 120km/h?
4. A cannonball shot with an intial velocity of 150m/s at an angle of 45 degrees follows a parabolic path and hits a balloon at the top of its trajectory. Ignoring air resistance, how fast is the cannonball going when it hits the balloon?
5. A vacationer floats lazily in the ocean with 93% of his body below the surface. The density of ocean water is 1,025 kg/m^3. What is the vacationer's average density?
6. What will be the final temperature of 100g of 25 degree C water when 100 g of 45 degree C iron nails are submerge in it. (The specific heat of iron is 0.12 cal/g. The specific heat of water is 1.00 cal/g.)
8. A weight suspended from a spring is seen to bob up and down over a distance of 40 centimeters twice each second. What is frequency? Its period? Its amplitude? Include units.
9. Balance the chemical equation and be sure to show your work!
___ CH4 + ____O2 → ____CO2 + _____H2O
10. How many grams of ozone, O3 (48 amu), can be produced from 96 grams of oxygen, O2(32amu), in the following reaction - show all work!
3 O2 → 2 O3
With excellent explanation and calculations, the problems are solved.