A bullet is fired from a rifle that is held 1.66 m above the ground in a horizontal position. The initial speed of the bullet is 1059 m/s. Calculate the time it takes for the bullet to strike the ground.

Therefore, the time it takes for the bullet to strike the ground is 0.582 seconds

Explanation:

h = ut + 0.5(gt²)

where;

h is the height above ground = 1.66 m

u is the initial velocity of the bullet vertically = 0

g is the acceleration due to gravity = 9.8 m/s²

From the equation above

1.66 = 0*t + 0.5*9.8*t²

1.66 = 4.9t²

t² = 1.66/4.9 = 0.3388

t = √0.3388

t = 0.582 seconds

Therefore, the time it takes for the bullet to strike the ground is 0.582 seconds

and 1and 1

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