How much work needs to be done to launch a baseball (145 g) at a speed of 108 MPH? The unit is Joule.

Given

m=145g=0.145kg (cause mass has unit kg)

v=108mph=48.28m/s

Find the work need

W=K (Work-Energy theorem)

K=1/2•m•v²

K=1/2•0.145•48.28²

K=168.99J

So, W=K=168.99J

Please give Brainliest

the minimum constant speed at which she can catch the train is 2.7 m/s

given:

acceleration = 0.6

time = 4.5 s

to find:

velocity = ?

formula used:

from 1st kinematic equation we get,

v = u + at

u = initial speed of train = 0 m/s

v = final speed of the train

a = acceleration of the train

t = time

solution:

from 1st kinematic equation we get,

v = u + at

u = initial speed of train = 0 m/s

v = final speed of the train

a = acceleration of the train

t = time

v = 0 + (0.6 × 4.5)

v = 2.7 m/s

the minimum constant speed at which she can catch the train is 2.7 m/s