Question

What is the difference between velocity and acceleration?

Answer 1

Speed has no direction while velocity does. For example, if I say that I'm running at 10 mph, I have given you my speed. If I say that I'm running 10 mph north, then I have given you my velocity. Acceleration is the rate of change in velocity. Imagine this: I am in my car and you look at me before I even press the gas pedal. You close your eyes then open them (imagine the blinking only took a second). Now, I'm going 10 mph north. You blink again. Now I'm going 20 mph north. Every second my velocity increased 10 mph north. This means my acceleration is 10 mph every second or 10 mi/h/s.

Answer 2

Acceleration is the rate at which velocity changes, which means that acceleration tells you how fast the velocity is changing. A large acceleration tells you that the velocity is changing quickly - a small acceleration tells you that the velocity is changing slowly - an acceleration of zero tells you that the velocity is not changing at all.

Acceleration tells you how the velocity changes - it doesn't tell how how much the velocity is! An object can have a large velocity and a small (or zero) acceleration - and vice versa.