Abullet is fired straight up from a gun with a muzzle velocity of 312 m/s. neglecting air resistance, what will be its displacement after 1.4 s? the acceleration of gravity is 9.8 m/s 2 . answer in units of m

427.196 m

Explanation:

u = Initial velocity = 312 m/s

t = Time = 1.4 s

s = Displacement

a = -9.8 m/s² (because the bullet is decelerating as the bullet is going straight up)

Equation of motion

So, Displacement at 1.4 seconds is 427.196 m

427.196 m

Explanation:

Given:

Initial velocity of the bullet, u = 312 m/s

Time, t = 1.4 s

Acceleration due to gravity, g = 9.8 m/s²

since the bullet is fired in the direction opposite to the direction of the acceleration due to the gravity, the acceleration will be negative

therefore,

From  Newton's equation of motion

where,  

s is the displacement

a is the acceleration

on substituting the respective values, we get

or

s = 436.8 - 9.604 = 427.196 m

b would be the answer