When sound waves are reflected back to the source, the reflected sound is called

Two pans of a balance are 24.1 cm apart. the fulcrum of the balance has been shifted 1.33 cm away from the center by a dishonest shopkeeper. by what percentage is the true weight of the goods being marked up by the shopkeeper? assume the balance has negligible mass. answer in units of %.

Photons with the highest energy have the longest period

Avehicle accelerates from 0 to 30 m/s in 10 seconds on a straight road