A fireworks mortar is launched straight upward from a pool deck platform 4 m off the ground at an initial velocity of 61 m/sec. The height of the mortar can be modeled by where h(t) is the height in meters and t is the time in seconds after launch. What is the maximum height

22.48m

Explanation:

Given that the pool deck platform is 4 m above the ground.

The initial velocity of mortar in the upward direction, u=21 m/s

At the maximum height, the velocity of the mortar will become zero.

So, the final velocity, v=0

Acceleration due to gravity, g = 9.81 m/ in the downward direction.

By using the equation of motion

On putting all the values, we have

s= 22.48 m

Hence, the mortar will reach a maximum height of 22.48m.

when jerome paddle in flowing river towards east the net speed of jerome will increase

so the net speed of jerome will be given as

now the speed of paul will be same as it is given as he is running on the ground

so

so here we can say since the speed of jerome is more so he will win the race

now as we know the distance so the time difference is given as

so jerome will reach first and the time difference will be 203.55 s or 3.4 min