Speed is how fast something moves. It's measured in units like miles per hour (mph), kilometers per hour (km/h), or meters per second (m/s).
Average speed is the total distance traveled divided by the total time taken. For example, if you drive 100 miles in 2 hours, your average speed is 50 mph.
Instantaneous speed is the speed at a specific moment. For example, your car's speedometer shows your instantaneous speed.
Velocity is speed with a direction. For example, driving north at 60 mph is a velocity.
Acceleration is how fast the speed changes. For example, a car speeding up is accelerating.
A person with his friend started from his house at 5 am and reached railway station which is 50 km away. First he travelled at 90km/hr for 20 min and then 120km/hr for 10 min.He dropped his friend at the station and started return journey to his house at 5.30 am and reached the house at 6.30 am. what is his speed for onward journey,return journey,average speed for the total journey, velocity of the onward journey,velocity of the return journey and velocity of the total journey?