What is the period of a 4.12 m long pendulum?

If all the forces acting on a book are balanced

Newton's first law can also be referred to as what?

The primary colors of light are?

A thin film of MgF₂ (n = 1.38) coats a piece of glass. Constructive interference is observed for the reflection of light with wavelengths of 500 nm and 625 nm. What is the thinnest film for which this can occur?

A rescue helicopter lifts a 72.3-kg person straight up by means of a cable. the person has an upward acceleration of 0.571 m/s2 and is lifted from rest through a distance of 8.41 m.

Why is thermal energy from the Sun transferred to Earth through electromagnetic waves instead of any other type of thermal energy transfer? Electromagnetic waves can carry energy through matter. Electromagnetic waves can travel through empty space.

Why do different elements emit different colors of light

In an experiment, 108 J of work was done on a closed system. During this phase of the experiment, 79 J of heat energy was added to the system. What was the total change in the internal energy of the system?

J. J. Thomsons experiments provided evidence that an atom

How does our sun differ from most other main sequence stars?