Answer:
(B)Speed - constant, Velocity - changing
Explanation:
The magnitude of the velocity ( speed ) has not changed as car is traveling constantly at 70 km/h. But we know the velocity is also having a direction component, and the car which was traveling South is now traveling East. As direction is changed, velocity is changed but as magnitude of velocity has not changed, the speed remain unchanged.
12km = 12000m
12000m / 4 m/s = 3000s
just under one hour
The correct answer would be 1.7 m/s:
Start with what you know. In the y-direction, we know the jumper must fall 15 meters and starts with 0 velocity in the y direction. You can also assume that the acceleration of gravity is pulling down on the jumper at 9.8 m/s. Once you have these three you can plug it into kinematic a equation to find time
x=Vot+1/2at^2
15=(0)t+1/2(9.8)(t)^2
t=1.75
You get time=1.75 seconds. Since this is a kinematics problem, both the x and y direction have the same amount of time. You can then see that the x displacement is 3 to avoid the rocks, and acceleration is 0 in the x direction because no force is speeding it up. Therefore you can use the same equation to find initial velocity and final velocity, which are gonna be the same because we have 0 acceleration:
X=Vot+1/2at^2
3=Vi(1.75)+1/2(0)(1.75)^
Vi=1.7
1.7 is your answer
I have my work in the picture I really like to make charts to help keep everything organized if that helps you
Answer:
Logically yes, because Newton's Third law state "When one body exerts a force on a second body, the second body simultaneously exerts a force equal in magnitude and opposite in direction on the first body."
If force wasn't pushing up then neither gravity is pulling down.
The reading on the scale is greater than your actual weight.