Answer:
62.601kJ
Explanation:
We have a force with a horizontal component given by the angle of 15°. So wue can take this component to calculate the total work done, that is,
Our values are,
,
Substituting in Work equation,
Potential energy does.
A book on the floor has negative potential energy relative to the seat
of your chair, zero potential energy relative to the floor, and a whole
bunch of positive potential energy relative to the ground if the floor
is the floor of the passenger jet in which you are cruising and dropped
your book on the floor.
Answer:
the ball's velocity was approximately 0.66 m/s
Explanation:
Recall that we can study the motion of the baseball rolling off the table in vertical component and horizontal component separately.
Since the velocity at which the ball was rolling is entirely in the horizontal direction, it doesn't affect the vertical motion that can therefore be studied as a free fall, where only the constant acceleration of gravity is affecting the vertical movement.
Then, considering that the ball, as it falls covers a vertical distance of 0.7 meters to the ground, we can set the equation of motion for this, and estimate the time the ball was in the air:
0.7 = (1/2) g t^2
solve for t:
t^2 = 1.4 / g
t = 0.3779 sec
which we can round to about 0.38 seconds
No we use this time in the horizontal motion, which is only determined by the ball's initial velocity (vi) as it takes off:
horizontal distance covered = vi * t
0.25 = vi * (0.38)
solve for vi:
vi = 0.25/0.38 m/s
vi = 0.65798 m/s
Then the ball's velocity was approximately 0.66 m/s
