Science
1.) While traveling along a level highway at a speed of 27 m/s (60 miles per hour), you shift the
vehicle into neutral and find that it takes 4.5 seconds to slow to 20 m/s (45 miles per hour.) Include in
your response:
a) What is the deceleration of your vehicle during these 4.5 seconds?
b) What force is applied by the air resistance acting on the car, assuming the mass of the car
to be 2000 kg?
2.) A 40-kg child runs at 8 m/s.
a) Calculate the child’s kinetic energy.
b) If the child could convert all of the kinetic energy you calculated in part (a), into upward motion, how
high could she jump?
3.) Calculate the overall efficiency to produce light in a fluorescent lamp from electrical energy
derived from a nearby nuclear power plant. This multistep process begins with the efficiency of a nuclear
power plant, rated at 35%; then the electrical energy is transmitted over transmission lines rated at 90%,
and finally the electrical energy used by the fluorescent bulb to produce light, rated at 20%. In your
response, show your work so that you can receive some partial credit.
4.) How much electrical energy is needed to heat the water in a hot water heater with a capacity of 40
gallons from 60°F to 110°F? How much will this cost at a rate of $0.13/kWh? Show your work and make sure to
answer both questions.
5.) What is the efficiency of an engine that has 2200 J of heat added during combustion and loses 1000 J
of heat in the exhaust?
PLACE THIS ORDER OR A SIMILAR ORDER WITH US TODAY AND GET A GOOD DISCOUNT
