Answer: 3.49 s
Explanation:
We can solve this problem with the following equation of motion:
(1)
Where:
is the final height of the ball
is the initial height of the ball
is the initial velocity (the ball was dropped)
is the acceleratio due gravity
is the time
Isolating :
(2)
(3)
Finally we find the time the ball is in the air:
(4)
Answer:
C
Explanation:
For a uniformly distributed mass, the center of gravity is also the geometric center. For this shape, the center is at point C.
Odd though it seems at first, gravity is pulling the cat down while the floor is pushing the cat up - in equal amounts. Forces are absolutely acting on the cat but they balance - so there is no net force.
In question 1, both of your answers are correct, but I don't understand the process you went through in the 'a' part.
R = v/I . That's a correct formula.
But it doesn't help you in this form, because you need to find I
So turn it into a helpful form ... Solve it for I, so it says I=something.
R= v/I
Multiply each side by I : R I = V.
Now divide each side by R: I= V/R .
THERE'S the equation you want.
I = V / R
I = 1.5 / 10 = 0.15 Amp.
That's slightly cleaner, although I don't really understand what you were actually thinking in that part.
But again ... You answered both parts correctly, and your process in b is fine.
