Question

suppose you hit a fly ball with an initial upward velocity of 20 feet per second.Which of the following equations would be a realistic model for the height of the ball after t seconds?
A. h=-16t^2+20t+300
B. h=-16t^2+20t+30
C.h=-16t^2+20t+3
D.h=-16t^2+200t+3.

Answer 1

you need a term which contributes a negative acceleration due to gravity. this will be of the form h = -gt^2 where g = 32 ft/s^2 or 9.8 m/s^2 on the surface of the Earth.

You also need a term which represents the ball going up with its initial upward velocity. This will be of the form vt where v is the initial velocity and t is the time in flight.

Finally, there will be a constant term which represents the height of the ball when it is hit.

That should be enough information to make the right choice.

Answer 2

You might find it helpful to remember the acronym SUVAT: read about it at https://sentynel.com/media/old/equations.html