Answer:
The resultant velocity of the helicopter is .
Explanation:
Physically speaking, the resulting velocity of the helicopter (), measured in meters per second, is equal to the absolute velocity of the wind (), measured in meters per second, plus the velocity of the helicopter relative to wind (), also call velocity at still air, measured in meters per second. That is:
(1)
In addition, vectors in rectangular form are defined by the following expression:
(2)
Where:
- Magnitude, measured in meters per second.
- Direction angle, measured in sexagesimal degrees.
Then, (1) is expanded by applying (2):
(3)
If we know that , , and , then the resulting velocity of the helicopter is:
The resultant velocity of the helicopter is .
D-It will become a temporary magnet because the domains will easily realign.
Answer:
B) the change in momentum.
Explanation:
The impulse is defined as the product between the force applied on an object (F) and the duration of the collision ():
(1)
We can rewrite the force by using Newton's second law, as the product between mass (m) and acceleration (a):
So, (1) becomes
Now we can also rewrite the acceleration as ratio between the change in velocity and change in time: . If we substitute into the previous equation, we find
And the quantity is equivalent to the change in momentum, .
Answer:
An object at rest does not move and an object in motion does not change its velocity, unless an external force acts upon it
Explanation:
This statement is also known as Newton's first law, or law of inertia.
It states that the state of motion of an object can be changed only if there is an external force (different from zero) acting on it: therefore
- If an object is at rest, it will remain at rest if there is no force acting on it
- If an object is moving, it will continue moving at constant velocity if there is no force acting on it
This phenomenon can be also understood by looking at Newton's second law:
F = ma
where
F is the net force on an object
m is the mass
a is the acceleration
If the net force is zero, F = 0, the acceleration of the object is also zero, a = 0: therefore, the velocity of the object does not change, and it will continue moving at the same velocity (which can be zero, if the object was at rest).
Determine the frequency and the speed of these waves. The wavelength is 8.6 meters and the period is 6.2 seconds. Now find speed using the v = f. λ equation<span>.</span>