To develop a product that warms peoples hands would you use an exothermic or endothermic reaction? Why?

Which ones are all renewable resources A. coal, biomass, solar B. coal, natural gas, oil C. hydroelectric, natural gas. solar D. hydroelectric, biomass, solar

On a cold winter day when the temperature is - 20∘C, what amount of heat is needed to warm to body temperature (37 ∘C) the 0.50 L of air exchanged with each breath? Assume that the specific heat of air is 1020 J/kg⋅K and that 1.0 L of air has mass 1.

Suppose you increase your walking speed from 4 m/s to 12 m/s in a period of 1 s. What is your acceleration?

You have a 90 W electrical appliance that is on 24 hours per day. At $0.51 per kWh, how much are you paying daily for electricity to operate this appliance? Show your calculations here:

In order for an object to move, the forces acting on it must be

A unit vector is used in the symbolic representation of the electric field. What physical units does the unit vector have? meters. The unit vector has no units. coulombs. The units depend on how it is used.

What's the definition of streak

The organization of notes into regular groups results in A. some notes sounding more prominent than others. B. all notes lasting for the same amount of time. C. patterns of long and short notes. D. a steady beat.

Sara is sitting in the back seat as her father drives at a constant speed. If Sara's father presses on the brakes quickly slowing the car down, what slows Sara down? A. air resistance on the inside of the car B.

A box of books has lessequalmore inertia than a box of cotton balls.