Answer:
jrirnr tn
Explanation:
and then we was just wondering what we should be talking to about to see how you are
There should be an option once two people answer the question
Answer:
The total energy of the object does not change is the true statement.
Explanation:
1. The force applied to the object is perpendicular to the movement so doesn't work on it, assuming the table is at the same height in all of its points the only energy we have to analyze is the kinetic energy , because the table top is frictionless by Newton's first law the velocity (v) doesn't change so the kinetic energy is constant and the total energy too.
2. There's no friction in this situation
3. As stated on 1. because the applied force is perpendicular to the movement of the object, there force doesn't work on it.
4. There are over one force on the object, the weight and the normal force table top exerts to the object.
So the only true statement is 1.
Answer: option b.
Explanation:
The kinetic energy of a spring with constant K is calculated as:
kinetic energy = (k/2)*x^2
Where x^2 is the displacement of the spring with respect to it's rest position.
This can be written as a function like:
x = A*cos(2*pi*f*t)
where:
A is the amplitude (the maximum distance that the spring can move in each direction)
f is the frequency (and 2*pi*f is the angular frequency)
and t is the variable, it represents the time.
Replacing this in the kinetic energy equation, we get:
kinetic energy = (k/2)*(A*cos(2*pi*f*t))^2
This is the same as the option b: b. 1/2kA^2cos^2(2πft)
Then the corrrect option is b.
I think you wrote 4900 twice so will use that as the distance. To solve this it is helpful to draw a picture. The drawing should be of a triangle. Since the driver is driving up at an angle, the 4900 ft will be the hypotenuse of the triangle. since we do not know the values of the other two sides of the triangle we cant solve for the altitude using Pythagorean theorem but we can solve using the sine function on our calculator. As sine of angle is equal to opposite over hypotenuse(sinθ=opposite/hypotenuse). Having θ and the hypotenuse we can solve for opposite or the altitude. using some algebra we get hypotenuse*sinθ=opposite or altitude. now to plug everything in and solve: 4900 ft*(sin(2°))=opposite or altitude=171 ft