Is the use of a toaster 100% efficient? Why or why not

Some students paint the inside of several boxes. They paint each box a different color. They observe that the inside of the box painted white looks brighter than the others. What is the most likely reason this box looks brighter?

What is one measurement needed to calculate the speed of an object? Direction Mass Time Velocity

Four elements arbitrarily labelled A, B, C, and D have electronegativities of 3.8, 3.3, 2.8, and 1.3, respectively. Place the compounds AB, AD, BD, and AC in order of increasing covalent character

If the pulley was not set so that the string was parallel to the track, what effect would this have on the acceleration of the system? what effect would this have on the normal force from the track? would this be a random or systematic error?

What does Kepler's second law of planetary motion imply?

Magnetic fields and electric fields are identical in that they both-

A toy helicopter begins flying across a field with a speed of 3 m/s and an acceleration of 0.8 m/s2. How long does it take the helicopter to reach a speed of 7 m/s?

A 50.0 kg child stands at the rim of a merry-go-round of radius 1.50 m, rotating with an angular speed of 3.00 rad/s. (a) what is the child's centripetal acceleration? incorrect: your answer is incorrect.

Do all types of waves need a medium to travel through

What feature of the ocean basin is formed when old oceanic crust is forced under continental plates