Answer: 1 m/s
Explanation:
We have an object whose position
is given by a vector, where the components X and Y are identified by the unit vectors
and
(where each unit vector is defined to have a magnitude of exactly one):
![r=[2 m + (2 m/s) t] i + [3 m - (1 m/s^{2})t^{2}] j](https://tex.z-dn.net/?f=r%3D%5B2%20m%20%2B%20%282%20m%2Fs%29%20t%5D%20i%20%2B%20%5B3%20m%20-%20%281%20m%2Fs%5E%7B2%7D%29t%5E%7B2%7D%5D%20j)
On the other hand, velocity is defined as the variation of the position in time:

This means we have to derive
:
![\frac{dr}{dt}=\frac{d}{dt}[2 m + (2 m/s) t] i + \frac{d}{dt}[3 m - (1 m/s^{2})t^{2}] j](https://tex.z-dn.net/?f=%5Cfrac%7Bdr%7D%7Bdt%7D%3D%5Cfrac%7Bd%7D%7Bdt%7D%5B2%20m%20%2B%20%282%20m%2Fs%29%20t%5D%20i%20%2B%20%5Cfrac%7Bd%7D%7Bdt%7D%5B3%20m%20-%20%281%20m%2Fs%5E%7B2%7D%29t%5E%7B2%7D%5D%20j)
This is the velocity vector
And when
the velocity vector is:

This is the velocity vector at 2 seconds
However, the solution is not complete yet, we have to find the module of this velocity vector, which is the speed
:


Finally:
This is the speed of the object at 2 seconds
Answer:
So Tammy must move with speed 4.76 m/s in opposite direction of Jackson
Explanation:
As per law of conservation of momentum we know that there is no external force on it
So here we can say that initial momentum of the system must be equal to the final momentum of the system
now we have

final they both comes to rest so here we can say that final momentum must be zero
now we have


Answer:

Explanation:
The word 'nun' for thickness, I will interpret in international units, that is, mm.
We will begin by defining the intensity factor for the steel through the relationship between the safety factor and the fracture resistance of the panel.
The equation is,

We know that
is 33Mpa*m^{0.5} and our Safety factor is 2,

Now we will need to find the average width of both the crack and the panel, these values are found by multiplying the measured values given by 1/2
<em>For the crack;</em>

<em>For the panel</em>

To find now the goemetry factor we need to use this equation

That allow us to determine the allowable nominal stress,


\sigma_{allow} = 208.15Mpa
So to get the force we need only to apply the equation of Force, where



That is the maximum tensile load before a catastrophic failure.
Refer to the diagram shown below.
When an athlete is in motion, he/she exerts a vertical force (the person's weight, W) on the ground. The ground exerts an equal and opposite force, N, the normal reaction on the athlete, so that W = N.
At the same time, the ground exerts a horizontal force, F, o n the athlete so that he/she does not slip.
The magnitude of the horizontal force is
F = μN = μW
where μ = the dynamic coefficient of friction.
Answer:
The horizontal force is μW,
where
W = the weight of the athlete and,
μ = the dynamic coefficient of friction.
Incomplete question.The complete question is here
What is the magnitude of the force needed to hold the outer 2 cm of the blade to the inner portion of the blade? The outer edge of the blade is 21 cm from the center of the blade, and the mass of the outer portion is 7.7 g. Even though the blade is 21cm long, the last 2cm should be treated as if they were at a point 20cm from the center of rotation.
Answer:
F= 0.034 N
Explanation:
Given Data
Outer=2 cm
Edge of blade=21 cm
Mass=7.7 g
Length of blade=21 cm
The last 2cm is treated as if they were at a point 20cm from the center of rotation
To Find
Force=?
Solution
Convert the given frequency to angular frequency
ω = 45 rpm * (2*pi rad / 1 rev) * (1 min / 60 s)
ω= 3/2*π rad/sec
Now to find centripetal force.
F = m×v²/r
F= m×ω²×r
Put the data
F = 0.0077 kg × (3/2×π rad/sec
)²× 0.20 m
F= 0.034 N