Answer:
Graph for object that is not moving: B
Graph for object that is speeding up: D
Explanation:
A.) In order to represent that an object is not moving, you must either show that there is no velocity (0 m/s) or show a position over time graph that is a horizontal line.
Because the position is the same as time increases, the graph shows that there the object must be at rest, as there is no change in position due to velocity. (Velocity must be 0m/s)
B.) In order to represent an object is speeding up, the position time graph must either be a positive exponential function, the velocity time graph must be a positive, linear line, or the acceleration over time graph must be a positive, horizontal line.
Why is D the correct answer? Because if an object is speeding up, you know that the value of its speed (velocity) is increasing at some rate. And since speeding up refers to positive change, the function of velocity over time graph must be a positive function.
Answer:
v = 9.04 m / s
Explanation:
For this exercise we can use the relation that the work of the non-conservative force (friction) is equal to the variation of the mechanical energy of the system.
W = Em_f - Em₀ (1)
Starting point. Lower slope
Em₀ = K = ½ m v²
highest point. Where is the skier at a height h
Em_f = U = m g h
The work of rubbing
W = -fr x
the negative sign is because the friction force opposes the movement.
Let's set a reference system where the x axis is parallel to the slope and the y axis is perpendicular
let's use trigonometry to break down the weight
cos θ = W_y / W
sin θ = Wₓ / W
W_y = W cos θ
Wₓ = W sin θ
Y axis
N - Wₓ = 0
N = mg sin θ
X axis
fr = m a
the friction force has the expression
fr = μ N
fr = μ mg sin θ
we look for the job
W = - μ mg sin θ x
where x is the distance along the slope
we substitute in 1
-μ mg sin θ x = mg h - ½ m v²
let's use trigonometry to find the distance x
tan 30 = h / x
x = h / tan 30
we substitute
-
= m gh - ½ m v²
we use
tan 30 = sin30 / cos30
v² = 2g h + 2 μ g h cos 30
v = 
let's calculate
v = 
v = 9.04 m / s
Answer:
rA = 9 i + 9 j
rB = 12 i - 9 j
rB - rA = 3 i - 18 j
so distance in between them
= √[3×3 + 18 × 18 )
= √(9+324)
= √333
= 18.3 m
Answer: Answer is B
Explanation: These are all explaining on how multipler different types of cells work together on how the body cooperates with other cells in order to maintain peace within the body however B using the process of elimination doesn't and says on the unicellular organisms work out the differnet parts in the body