algebra

posted by .

At a crime scene, police officers find a murder victim in a tub full of warm water. A thermometer shows that the water temperature is 75 degrees F and the air temperature is 70 degrees F. It is known that most people fill a tub with water at 100 degrees F. Find Newton's Law of cooling and use it to model the temperature of the water in the tub(using a heat transfer coefficient of k=0.018). To the nearest whole minute, how long has the bathtub water been cooling?
I found the equation of T(t)=TA+(TH-TA)e^-kt

  • algebra -

    75 = 70+(100-70)e^-.018t
    t = 99.54
    or 100 minutes

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

  1. Chemistry

    A person falls in water at 0 degrees C. After 20 minutes of exposure, they are suffering acute hypothermia, as their core body temperature has dropped to 30.0 degrees C. Assume that a person’s heat capacity can be approximated by …
  2. Physics

    You decide to take a nice hot bath but discover that your thoughtless roommate has used up most of the hot water. You fill up the tub with 270 kg of 30.0°C water and attempt to warm it further by pouring in 5.00 kg of boiling water …
  3. College Algebra Application

    Newton's Law of Cooling T(t)=T0+(T1-T0)e^-kt The police discover the body of a murder victim. Critical to solving the crime is determining when the murder was committed. The coroner arrives at the murder scene at 12:00pm. She immediately …
  4. Physics

    A bathtub of icy water at 32 degrees farenheit holds 17 gallons. You put in a 25 pound watermelon with a temperature of 100 degrees farenheit. If you wrap the tub completely in blankets so it does not lose any heat, what will be the …
  5. Newton's Law of Cooling

    You are a forensic doctor called to a murder scene. When the victim was discovered, the body temperature was measured and found to be 20°C. You arrive one hour later and find the body temperature at that time to be 18°C. Assuming …
  6. algebra

    A thermometer is guaranteed to give a temperature no more than 1.2 degrees Fahrenheit from the natural temperature. If the thermometer reads 28 degrees Fahrenheit, write and solve an eqution to find the maximum and minimum temperatures …
  7. algebra

    At a crime scene, police officers find a murder victim in a tub full of warm water. A thermometer shows that the water temperature is 75 degrees F and the air temperature is 70 degrees F. It is known that most people fill a tub with …
  8. Algebra

    The rate at which water evaporates from a certain reservoir depends on the air temperature. The table below shows the number of acre-feet (af) of water per day that evaporate from the reservoir for various temperatures in degrees Fahrenheit. …
  9. physics

    Ideally, when a thermometer is used to measure the temperature of an object, the temperature of the object itself should not change. However, if a significant amount of heat flows from the object to the thermometer, the temperature …
  10. PHYSICS

    Ideally, when a thermometer is used to measure the temperature of an object, the temperature of the object itself should not change. However, if a significant amount of heat flows from the object to the thermometer, the temperature …

More Similar Questions