Answer:
acceleration 8 km/h/s south
Explanation:
First of all, let's remind that a vector quantity is a quantity which has both a magnitude and a direction.
Based on this definition, we can already rule out the following two choices:
distance: 40 km
speed: 40 km/h
Since they only have magnitude, they are not vectors.
Then, the following option:
velocity: 5 km/h north
is wrong, because the car is moving south, not north.
So, the correct choice is
acceleration 8 km/h/s south
In fact, the acceleration can be calculated as

where
v = 40 km/h is the final velocity
u = 0 is the initial velocity
t = 5 s is the time
Substituting,

And since the sign is positive, the direction is the same as the velocity (south).
Here We can use principle of angular momentum conservation
Here as we know boy + projected mass system has no external torque
Since there is no torque so we can say the angular momentum is conserved

now we know that
m = 2 kg
v = 2.5 m/s
L = 0.35 m
I = 4.5 kg-m^2
now plug in all values in above equation

![1.75 = [4.5 + 0.245]\omega](https://tex.z-dn.net/?f=1.75%20%3D%20%5B4.5%20%2B%200.245%5D%5Comega)


so the final angular speed will be 0.37 rad/s
Answer: Next time you create a question, add an image or PDF. Because I do not know the question. So, may you please create a new question?
Answer:
She does a work of 689.44 J in the snow.
Explanation:
A force is said to do work when it alters the state of motion of a body. The work of the force on that body will be equivalent to the energy needed to move it.
In other words, Work is a form of energy transmission between bodies. In order to carry out work, a force must be exerted on a body and it must move.
The work is equal to the product of the force times the distance and the cosine of the angle that exists between the direction of the force and the direction that the moving point or object travels:
W= F*d* cos Ф
Work W is measured in joules (J), force is measured in newtons (N), and displacement in meters (m).
In this case:
- F= 180 N
- d=5 m
- Ф= 40 degrees
Replacing:
W= 180 N*5 m* cos 40
Solving:
W= 689.44 J
<u><em>She does a work of 689.44 J in the snow.</em></u>
Answer:
The duck floats on water because his/her density is less than the density of water
Explanation: