Question

1. A baseball is thrown horizontally at 45 m/s. The ball slows down at a rate of 5 m/s?

Answer 1

Answer:

Explanation:

a )

initial velocity u = 45 m/s

acceleration a = - 5 m/s²

final velocity v = 0

v = u - at

0 = 45 - 5 t

t = 9 s

b )

s = ut - 1/2 at²

= 45 x 9 - .5 x5x 9²

405 - 202.5

202.5 m

2 )

a )

s = ut + 1/2 a t²

u = 0

s = 1/2 at²

= .5 x 9.54 x 6.5²

= 201.5 m

b )

v = u + at

= 0 + 9.54 x 6.5

= 62.01 m / s

3

a )

acceleration = (v - u) / t

= (34 - 42) / 2.4

= - 3.33 m /s²

b )

v² = u² - 2 a s

34² = 42² - 2 x 3.33² s

s = 27.41 m

c )

Average velocity

Total displacement / time

= 27.41 / 2.4

= 11.42 m /s

4 )

a )

v = u + at

v = 0 + 3 x 4

= 12 m /s

b )

s = ut + 1/2 a t²

= o + .5 x 3 x 4²

= 24 m