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
No. I do not agree with Stefan. Quite the contrary. I disagree
with his description of "<span>angle of incidence" as the angle between
the surface of the mirror and the incoming ray.
The correct description of "angle of incidence" is </span><span>the angle between
the NORMAL TO the surface of the mirror and the incoming ray.
Thus, the true angle of incidence is the complement of the angle that
Stefan calculates or measures.</span>
Time = (distance) / (speed)
<em></em>
Time = (450 km) / (100 m/s)
Time = (450,000 m) / (100 m/s)
Time = <em>4500 seconds </em>(that's 75 minutes)
Note:
This is about HALF the speed of the passenger jet you fly in when you go to visit Grandma for Christmas.
If the International Space Station flew at this speed, it would immediately go ker-PLUNK into the ocean.
The speed of the International Space Station in its orbit is more like 3,100 m/s, not 100 m/s.
Answer:
3,150,000N
Explanation:
According to Newton's second law;
F = mass * acceleration
Given
Mass = 45000kg
acceleration = 70m/s^2
Substitute
F = 45000 * 70
F = 3,150,000N
Hence the force required to be produced by the rocket engines is 3,150,000N
