Answer:
The velocity of the ball before it hits the ground = 21.4m/s
Explanation:
The question can be solved as a projectile problem. One of the main characteristics of the parabolic motion is the symmetry it has as long as the initial height is equal to the final height with respect to a reference system, the vertical displacement of the horizontal displacement being independent.
The vertical component of velocity is 13m/s
The horizontal component is 17m/s
The ball's pathway is defined by a right angle triangle .
Using Pythagorean
Let vertical component be a
Let horizontal component be b
Let the speed of the ball before hitting the ground be c
Pythagorean is given by:
a^2 + b^2 = c^2
13^2 + 17^2 = c^2
169 + 289 = c^2
458 = c^2
Sqrt(458) = c
21.4 m/s = c
If their volumes are equal, then the denser one has more mass.
Answer:
I would say B
Explanation:
the other ones don't seem right
True
Explanation: Since the cornea is a curved surface, it acts like a convex lens and begins to focus the light rays. The light then passes through the pupil and hits the lens of the eye. The lens, also convex, further focuses the light so that it will hit the retina at the back of the eyeball.
Answer:
The radius of curvature changes so that centripetal acceleration is similar along the entire roller coaster.
Explanation:
We know that the centripetal acceleration is directly proportional to the tangential velocity and inversely proportional to the radius of curvature:
By energy conservation (and common sense), we know that the speed at the top of the roller coaster is smaller. Therefore if the roller coaster has similar accelerations (therefore also similar normal forces) at the top and at the bottom, it is necessary that the difference in speed be compensated with the radius of curvature, i.e. smaller radius at the top than at the bottom.