Explanation:
Speed has only magnitude.
Velocity has magnitude and direction.
"A bike goes 25 m/s toward main street."
This includes a direction, so it is velocity (V).
"A person walks 4 mph."
This has only magnitude, so it is speed (S).
"A plane flies 200 m/s."
This has only magnitude, so it is speed (S).
"A bird flies 100 mph due south."
This includes a direction, so it is velocity (V).
In middle school, the formula you'll use most often when you're
working with acceleration is . . .
Acceleration = (change in speed during some time) / (time for the change)
These are two questions and two answers.
Part 1. Fin the value of the ration of velocity C to velocity D.
Answer: 2
Explanation:
1) Formula: momentum = mass * velocity
2) momentum C = mass C * velocity C
3) momentum D = mass D * velocity D.
4) C and D have the same momentum =>
mass C * velocity C = mass D * velocity D
5) mass C = (1/2) mass D => mass C / mass C = 1/2
6) use in the equation stated in the point 4)
velocit C / velocity D = mass D / mass C
using the equation stated in point 5:
mass D / mass C = 1 / [ mass C / mass D] = 1 / [1/2] = 2
=>
7) velocity C / velocity D = mass D / mass C = 2
Part 2: <span>ratio of kinetic energy C to kinetic energy D.
</span>
Answer: 2
Explanation:
1) formula: kinetic energy KE = (1/2) mass * (velocity)^2
2) KE C = (1/2) mass C * (velocity C)^2
3) KE D = (1/2) mass D * (velocity D)^2
4) KE C / KE D =
(1/2) mass C * (velocity C)^2 mass C (velocity C)^2
--------------------------------------- = --------------- * ---------------------- = (1/2) * (2)^2
(1/2) mass D *( velocity D)^2 mass D v(velocity D)^2
= 4 / 2 = 2
The answer is D. Small object made of ice and dust that orbits the Sun and forms a coma as it approaches the Sun.
