How are electromagnetic waves different from mechanical waves? A Electromagnetic waves need a medium to travel through; mechanical waves don't. incorrect answer
B Electromagnetic waves can travel through water; mechanical waves can only travel through solid matter. incorrect answer
C Electromagnetic waves can travel through empty space; mechanical waves can't. incorrect answer
D Electromagnetic waves are long chains of vibrating molecules; mechanical waves aren't. incorrect answer

Two horses begin at rest. after a few seconds, horse a is traveling with a velocity of 10 m/s west, while horse b is traveling with a velocity of 13 m/s west. which horse had a greater acceleration? a. horse a because its change in velocity was greater than horse b's in the same time. b. horse b because its change in velocity was greater than horse a's in the same time. c. horse b because its change in velocity was the same as horse a's, but it took less time. d. both horses had the same acceleration.