A ball is launched horizontally at a speed of 4.0m/s from the top of a cliff that is 24.6 meters high. Where in the ball's trajectory is the horizontal speed a maximum? Explain how you know.

The horizontal speed of the ball is constant where there is little resistance from the air

Explanation:

From the given parameters of the ball, we have;

The horizontal speed of the ball = 4.0 m/s

The height of the cliff from which the ball is launched = 24.6 meters

The direction in which the ball is launched = Horizontally

The components of the forces acting on the ball are;

The vertical force = The Earth's gravitational attraction

The horizontal force = 0 N (There are no horizontal forces acting on the ball)

According to Newton's first law of motion, the ball will continue in its uniform motion or in its rest state unless acted upon by a force

Therefore, given that there are no horizontal forces component acting on the ball, (little air resistance) the ball will continue with the initial horizontal velocity, such that the horizontal velocity of the ball remains constant.

work: w = fd (given)

work done by chet   =50*1 = 50 j

work done by mika =40*2 = 80 j

work done by sara =30*1.5 = 45 j

work done by bill =60*0.5 = 30 j

students in order from the greatest amount of work done to the least is mika> chet> sara> bill

hence option (b) is correct.

sleep paralysis is a parasomnia, events associated with sleep.

sleep paralysis happens when you are in the middle of waking up or falling asleep. it is the feeling of being conscious but unable to move. it definitely involves hallucinations.

i had a friend that had sleep paralysis and he told me a story one time where he was laying in bed and he couldn't move his body no matter how hard he tried and there was someone standing in the corner of his room coming towards him. he couldn't move and you can't "wake up" because you are already conscious. sometimes sleep paralysis can be triggered by frequent waking up during the night based off of multiple trips to the bathroom, or if you had ever been abused, sleep paralysis can start happening from things like that.