why does carrying furniture up four flights of stairs require twice as much work as caring furniture up two flights of stairs

An astronaut walking outside a space station can be seen, but not heard. The only way to communicate is through radio transmissions. what type of wave is this? how do you know?

Describe how the ringing sound of a telephone travels through air

What kind of star gives rise to a type i supernova? a. white dwarf stars b. massive main sequence stars c. red giant stars?

An object will appear the color that is Refracted Reflected Longest Separated

In the diagram above, a heavy box is being lifted. what is the function of the pulley

The process of changing the energy of a system by means of force. Force * Diatance

A gnat takes off from one end of a pencil and flies around erratically for 18.6 seconds before landing on the other end of the same pencil. If the gnat flew a total distance of 7.15 meters, and the pencil is 6.

An apple falls from an apple tree growing on a 20° slope. the apple hits the ground with an impact velocity of 16.5 m/s straight downward. what is the component of the apple's impact velocity parallel to the surface of the slope?

Objects falling through the air experience a type of friction called air resistance. true or false

How big is a wifi pulse signal coming from your router? A) 10 meters B) 15 meters C) 5-10 meters D) 20-30 meters