This force on compass dials is an example of a force that a. needs electricity to act. b. acts through particles in the air c. acts only on contact. d. acts at a distance.

Hydrogen atoms are excited by a laser to the =4n=4 state and then allowed to emit. what is the maximum number of distinct emission spectral lines (lines of different wavelengths) that can be observed from this system? 8 6 2 7 4 5 1 3 calculate the wavelength of the 4⟶14⟶1 transition. =λ=

Find the mass by adding the numbers from the three sliders

Match each type of lever with the correct diagram. 1. first-class 2. third-class 3. second-class