Answer:
Velocity of the passenger = 78.8[km/h]
Explanation:
In order to solve this problem, we must observe the train from a distant point of the train. In this way we can observe that the train moves at 80[km/h] relative to the ground.
In such a way that the passenger moves in a direction contrary to the movement of the train.
![v_{pass}=80-1.2\\ v_{pass}=78.8[km/h]](https://tex.z-dn.net/?f=v_%7Bpass%7D%3D80-1.2%5C%5C%20v_%7Bpass%7D%3D78.8%5Bkm%2Fh%5D)
The Observer located outside the train will see how the passenger moves away at 78.8 [km / h] and not at 80[km/h] which is the speed of the train.
The moon orbits the earth in the same direction as the earth, like if you had a ball on a string and you started spinning, the ball would spin the same direction.<span />
Answer:
Positive velocity and negative acceleration
Explanation:
An object moving in the positive direction has a positive velocity.
An object that's slowing down while moving in the positive direction has a negative acceleration.
Answer:
392 N
Explanation:
Draw a free body diagram of the rod. There are four forces acting on the rod:
At the wall, you have horizontal and vertical reaction forces, Rx and Ry.
At the other end of the rod (point X), you have the weight of the sign pointing down, mg.
Also at point X, you have the tension in the wire, T, pulling at an angle θ from the -x axis.
Sum of the moments at the wall:
∑τ = Iα
(T sin θ) L − (mg) L = 0
T sin θ − mg = 0
T = mg / sin θ
Given m = 20 kg and θ = 30.0°:
T = (20 kg) (9.8 m/s²) / (sin 30.0°)
T = 392 N