There are loads of similarities, but there are differences and that's what you want!
Speed- Is usually referring to how fast an object moves, it is calculated by space per unit.
Velocity- Refers to the rate at which said object changes position in a certain direction. Usually calculated by the displacement of space per unit.
SO it sounds the same, but simple answer Velocity deals with direction, and speed does not!
Answer:
Gravity is the only force acting on a falling ball because of free fall. Since gravity is unbalanced it accelerates an object and the velocity increases as an object falls due to gravity pushing it. The acceleration due to gravity is 9.8 m/s^2.
Answer; Ultrasonic waves (sounds having frequency greater than 20,000 Hz) are used in sonar because: ... Ultrasonic waves can penetrate water to long distances (because of their high frequency and very short wavelength), but ordinary sound waves or infrasonic waves cannot penetrate water to such long distances.
Yes. Partly. Also on the size and shape of the object, and also on what material it's IN at the time ... like air, water, Helium, Jello, etc.