1. A 2,000.0 lb car with a speed of 90.0 m/s brakes to a stop. How many calories of heat are generated by the brakes as a result?
2. A 50.0 g gold spoon at 10.0 °C is placed in a cup of how water 95.0 °C. How much heat does the water lose to the spoon if the spoon reaches a temperature of 59.0 °C?
3. A 10.00 kg block of ice at 5°C is added to a picnic cooler. How much heat will the ice remove as its melts to water at 0 °C?
4. A heat engine has a source of 1400.0 cal and exhausts 300.0 cal, converting the rest into work. How much mechanical work was done?