Answer:
a) K = 49.5 J b) k = 1378 N / m c) ΔE = 34 J d) μ = 0.399
Explanation:
For this exercise we will use the concepts of energy
a) The initial kinetic energy is
K = ½ m v²
K = ½ 3.96 5²
K = 49.5 J
b) let's use energy conservation
Em₀ = K = ½ m v²
= Ke = ½ k x²
Em₀ =
½ m v² = ½ k x²
k = m v² / x²
k = 3.96 5² / 0.268²
k = 1378 N / m
c) Let's calculate the final energy of the spring
= Ke = ½ k x²
= ½ 1378 0.15²
= 15.5 J
The initial energy is the kinetics of the block
Em₀ = 49.5 J
The lost energy is the difference with the initial
ΔE = - Em₀
ΔE = 15.5 - 49.5
ΔE = - 34 J
the negative sign means that the energy dissipates
d) For this part we use the concept of work
W = F d cos θ = ΔK
In this case the force is the friction force that always opposes displacement, so the angle 180 ° and cos 180 = -1
W = -fr d = ΔK
The force of friction is
fr = μ N
With Newton's second law
N-w = 0
N = W = mg
Let's calculate
-μ mg d = Kf -K₀o
μ = K₀ / mgd
μ = 49.5 / (3.96 9.8 3.20)
μ = 0.399
Answer:
Below is the calculation of all the required quantities. From the calculations, Vx must change, the velocity before hitting the ground must change and the angles also must change.
Explanation:
Below is an attachment that contains the calculation steps.
Thank you for reading.
Velocity vs. time graph shows the acceleration as a slope whereas displacement vs. time graph shows the velocity as a slope. So, the given statement is false.
Answer: Option B
<u>Explanation:</u>
To understand the acceleration graphically, consider the x axis of the graph as the run and the y axis as the velocity rise. Now, as we all know that,
We can estimate this through the graph. let's draw the motion of an object with time if it's velocity is changing in every second by 4 m/s. Now if we draw this on graph, we will see that there is a slope between the two corresponding values of time and velocity. This slope defines the acceleration for the object with time.
Now, in the same way, if we draw a distance and time graph respective to the y and x axis; we'll get a slope which defines the velocity of the object i.e. change in distance with time.
Hence, with a velocity vs time graph, we get the slope for acceleration whereas with the distance and time graph, we get the slope for velocity. So both the cases, we see there is no velocity slope on an acceleration and time graph. Hence the statement is false.
They are held through electrons