The height of an object tossed upward with an initial velocity of 136 feet per second is given by the formula h = −16t2 + 136t, where h is the height in feet and t is the time in seconds. find the time required for the object to return to its point of departure.

An electric clothes dryer has a resistance of 8 ohms. it draws 30 a of current. what is the voltage, in volts, of the wall outlet that it is plugged into?

Which of the following is the main energy source for the sun? a. fission of hydrogen b. fusion of hydrogen c. fusion of helium d. fission of iron

The heater element of a 120 v toaster is a 5.4 m length of nichrome wire, whose diameter is 0.48 mm. the resistivity of nichrome at the operating temperature of the toaster is 1.3 × 10-6 ω·m. the toaster is operated at a voltage of 120 v. (a) what is the power drawn by the toaster? (b) if the cost of electricity is 12 ¢ per kilowatt-hour, and it takes 2 minutes to toast bread, how much does it cost for toasted bread? (c) when the heater element is at room temperature, is the resistivity in the nichrome wire greater than, less than, or equal to it’s resistivity when at operating temperature? explain.